A high-load three-way flow impeller and its motor

Abstract

The present invention discloses a high-load three-dimensional flow impeller and its motor. The high-load three-dimensional flow impeller includes: an impeller body and a plurality of blades with the same shape arranged on the impeller body. The center of the impeller body has a shaft hole, and the plurality of blades are arranged in a spiral pattern centered on the axis of the impeller body. The impeller body is frustum-shaped. In the present invention, the impeller body is frustum-shaped, which can increase the impeller diameter to the maximum limit on the premise of ensuring the gas flow space, thereby increasing the impeller load and reducing the rotational speed.

Description

Technical Field

[0001] The present invention belongs to the technical field of motors, and particularly relates to a high-load three-dimensional flow impeller and its motor. Background Art

[0002] With the increasing maturity of the brushless motor market for vacuum cleaners, the demand for brushless motors with small volume and high power (such as over 450W) in the market is increasing; correspondingly, along with the small volume (due to space limitations, a small volume is inevitably accompanied by a relatively small diameter and small load impeller), high power will inevitably bring extremely high speeds (over 120,000 revolutions per minute). The problems brought by extremely high speeds are reflected in: the strength of the fan impeller, the life of the bearing, the strength of the motor structure, motor heating, process precision requirements, noise, and the cost of the motor.

[0003] Therefore, one of the main ways to solve the current problems is to reduce the speed under the condition that the volume and power of the motor remain unchanged. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention proposes a high-load three-dimensional flow impeller and its motor.

[0005] In order to achieve the above object, the technical solution of the present invention is as follows:

[0006] On the one hand, the present invention discloses a high-load three-dimensional flow impeller, including: an impeller body and a plurality of blades with the same shape arranged on the impeller body. The center of the impeller body has a shaft hole, and the plurality of blades are arranged in a spiral pattern centered on the axis of the impeller body. The impeller body is frustum-shaped, and the diameter of the impeller body near its air inlet side is smaller than the diameter of the impeller body near its air outlet side.

[0007] The present invention discloses a high-load three-dimensional flow impeller. The impeller body is frustum-shaped. On the premise of ensuring the gas flow space, the impeller diameter is maximally increased to increase the impeller load and reduce the speed.

[0008] Based on the above technical solution, the following improvements can be made:

[0009] As a preferred solution, the ratio of the inlet area S1 to the outlet area S2 of the impeller body is between 1 and 1.3;

[0010] S1 = (D2 2 *π / 4) - (D1 2 *π / 4);

[0011] S2 = (D4 2 *π / 4) - (D3 2 *π / 4);

[0012] Among them, D1 is the circle tangent to the leading edge of the blade and the hub surface of the impeller; D2 is the circle tangent to the outermost side of the leading edge of the blade; D3 is the circle tangent to the trailing edge of the blade and the hub surface of the impeller; D4 is the circle tangent to the outermost side of the trailing edge of the blade.

[0013] Adopting the above preferred scheme, within this proportional range of the inlet and outlet areas of the impeller, when the gas flows through the impeller passage, the change in gas velocity in the passage is reduced, and the phenomenon of gas separation from the blade due to the velocity change is thus reduced, thereby reducing the eddy current loss and improving the aerodynamic efficiency.

[0014] As a preferred scheme, the number of blades is between 7 and 9; the profile curves K1 and K2 of each blade are both spatial curves fitted by using cubic Bessel curves;

[0015] Among them, the profile curve K1 is the profile curve tangent to the side of the blade close to the hub surface of the impeller;

[0016] The profile curve K2 is the outermost profile curve of the side of the blade far from the hub surface of the impeller.

[0017] Adopting the above preferred scheme, it has better aerodynamic efficiency.

[0018] As a preferred scheme, the angle β1 between the leading edge of the innermost blade close to the hub surface of the impeller and the circumferential tangential direction is between 45 and 47 degrees;

[0019] The angle β1' between the leading edge of the outermost blade and the circumferential tangential direction is between 23 and 25 degrees;

[0020] The angle β2 between the trailing edge of the innermost blade close to the hub surface of the impeller and the circumferential tangential direction is between 48 and 52 degrees;

[0021] The angle β2' between the trailing edge of the outermost blade and the circumferential tangential direction is between 30 and 35 degrees;

[0022] The included angle between the straight line passing through the center of the impeller from the outermost point of the leading edge of the blade and the straight line passing through the center of the impeller from the outermost point of the trailing edge of the blade is the blade wrap angle θ, and the blade wrap angle θ is between 88 and 92 degrees.

[0023] Adopting the above preferred scheme, it has better aerodynamic efficiency.

[0024] As a preferred scheme, the included angle between the profile curve at the outer end of the trailing edge of the blade and the horizontal plane is the trailing edge bevel angle α of the blade, and the trailing edge bevel angle α of the blade is between 3 and 5 degrees.

[0025] Adopting the above preferred scheme, it has better aerodynamic efficiency, and the trailing edge bevel angle α of the blade effectively inhibits the phenomenon of trailing edge separation when the gas flows out of the impeller.

[0026] On the other hand, the present invention also discloses a motor, including: a housing, a wind cover, a bracket, a rear cover plate, a fixed impeller, an iron core, a rotor, a PCB electronic control board, and any one of the above high-load three-dimensional flow impellers.

[0027] As a preferred solution, heat dissipation holes are provided at a position in the inner ring of the housing close to the iron core.

[0028] By adopting the above preferred solution, better heat dissipation can be achieved.

[0029] As a preferred solution, the ratio of the opening area S3 of the housing to its inner ring area S4 is between 0.08 and 0.1.

[0030] By adopting the above preferred solution, the heat dissipation effect is better.

[0031] As a preferred solution, a plurality of inner ring support ribs and outer ring support ribs are provided at intervals on the inner wall of the housing, and the length L1 of the inner ring support ribs is half of the length L2 of the outer ring support ribs.

[0032] By adopting the above preferred solution, good balance can be achieved in both aspects of aerodynamic noise and aerodynamic efficiency. As a preferred solution, the shaft hole is a stepped structure, with a section away from the fixed impeller being a clearance section L3 and a section close to the fixed impeller being an interference section L4, and the ratio of L3 to L4 is between 0.5 and 0.6.

[0033] By adopting the above preferred solution, a transition fit is adopted between the moving impeller and the rotor shaft, eliminating the risk of the moving impeller disengaging from the shaft during high-speed rotation, and the reliability is stable. Description of the Drawings

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0035] Figure 1 It is a side view of the high-load three-dimensional flow impeller provided by the embodiment of the present invention.

[0036] Figure 2 It is a top view of the high-load three-dimensional flow impeller provided by the embodiment of the present invention (marked with D1, D2, D3, D4).

[0037] Figure 3 It is a top view of the high-load three-dimensional flow impeller provided by the embodiment of the present invention (marked with K1, K2).

[0038] Figure 4The third-order Bessel curve graph provided by the embodiment of the present invention.

[0039] Figure 5 The side view of the high-load three-dimensional flow impeller provided by the embodiment of the present invention (marked with β1, β1').

[0040] Figure 6 The top view of the high-load three-dimensional flow impeller provided by the embodiment of the present invention (marked with β2, β2').

[0041] Figure 7 The top view of the high-load three-dimensional flow impeller provided by the embodiment of the present invention (marked with θ, α).

[0042] Figure 8 The structural schematic diagram of the motor provided by the embodiment of the present invention.

[0043] Figure 9 The partial structural schematic diagram of the motor provided by the embodiment of the present invention.

[0044] Figure 10 The partial structural schematic diagram of the housing provided by the embodiment of the present invention.

[0045] Figure 11 The partial cross-sectional view of the upper half of the motor provided by the embodiment of the present invention.

[0046] Figure 12 The schematic diagram of the streamline of the CFD simulation flow field provided by the embodiment of the present invention.

[0047] Figure 13 The schematic diagram of the vector flow velocity of the CFD simulation flow field provided by the embodiment of the present invention.

[0048] Figure 14 The vector meridional flow velocity diagram of the CFD simulation impeller section provided by the embodiment of the present invention.

[0049] Figure 15 The test data of the air performance based on the IEC60312 test provided by the embodiment of the present invention.

[0050] Figure 16 The air performance curve graph based on the IEC60312 test provided by the embodiment of the present invention.

[0051] Wherein: 1 - high-load three-dimensional flow impeller, 11 - impeller body, 12 - blade, 13 - shaft hole, 2 - housing, 21 - inner ring support rib, 22 - outer ring support rib, 3 - wind cover, 4 - bracket, 5 - rear cover plate, 6 - stationary impeller, 7 - iron core, 8 - rotor, 9 - PCB electronic control board, 10 - heat dissipation hole. Specific embodiments

[0052] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0053] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0054] The expression "including" an element is an "open-ended" expression, which only means that there is a corresponding component and should not be construed as excluding additional components.

[0055] In order to achieve the object of the present invention, in some embodiments of a high-load three-dimensional flow impeller and its motor, as Figure 1 shown, a high-load three-dimensional flow impeller includes: an impeller body 11 and a plurality of blades 12 with the same shape arranged on the impeller body 11. The center of the impeller body 11 has a shaft hole 13. The plurality of blades 12 are arranged in a spiral around the axis 11 of the impeller body. The impeller body 11 is frustum-shaped, and the diameter of the impeller body 11 near its air inlet side is smaller than the diameter of the impeller body 11 near its air outlet side.

[0056] According to the impeller theoretical circumferential speed U = πDn / 60, where: D is the impeller diameter; n is the rotational speed, it can be seen that the magnitude of the rotational speed n is related to the impeller diameter. The larger the diameter, the lower the rotational speed.

[0057] The impeller body 11 is frustum-shaped, and the size of the frustum cone apex angle ε directly affects the area ratio of the impeller inlet and outlet, indirectly affects the impeller flow field change, and thus affects the aerodynamic efficiency of the impeller. Through simulation calculation and experimental verification, the frustum cone apex angle ε is between 60 and 65 degrees, and its inlet and outlet area ratio is within a reasonable range. ε

[0058] The present invention discloses a high-load three-dimensional flow impeller 1. The impeller body 11 is frustum-shaped, and the diameter of the impeller body 11 gradually increases along its axial direction from one end to the other end. On the premise of ensuring the gas flow space, the impeller diameter is maximally increased to increase the impeller load and reduce the rotational speed.

[0059] As Figure 2 shown, in order to further optimize the implementation effect of the present invention, in some other embodiments, the other characteristic technologies are the same, and the difference is that the ratio of the inlet area S1 to the outlet area S2 of the impeller body 11 is between 1 and 1.3;

[0060] S1 = (D2 2 * π / 4) - (D1 2 * π / 4);

[0061] S2 = (D4 2 * π / 4) - (D3 2 * π / 4);

[0062] Wherein, D1 is the circle tangent to the leading edge of blade 12 and the hub surface of the impeller; D2 is the circle tangent to the outermost side of the leading edge of blade 12; D3 is the circle tangent to the trailing edge of blade 12 and the hub surface of the impeller; D4 is the circle tangent to the outermost side of the trailing edge of blade 12.

[0063] With the above preferred scheme, within this proportional range of the inlet and outlet areas of the impeller, when the gas flows through the impeller passage, the change in gas velocity in the passage is reduced, and the phenomenon of gas separation of blade 12 is generated, thereby reducing the eddy current loss and improving the aerodynamic efficiency. Since the passage area continuously expands, the flow velocity gradually slows down, the pressure gradually increases, the static energy of the actual work in the impeller increases and the kinetic energy decreases, and the efficiency is improved.

[0064] As Figure 3 shown, in order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, the difference is that the profile curve K1 and profile curve K2 of each blade 12 are both space curves fitted by using the cubic Bézier curve;

[0065] Wherein, the profile curve K1 is the profile curve tangent to the side of blade 12 close to the hub surface of the impeller;

[0066] The profile curve K2 is the outermost profile curve of the side of blade 12 far from the hub surface of the impeller.

[0067] With the above preferred scheme, the shape of blade 12 is a space blade 12, and the drawing of its blade 12 shape is also different from the traditional single circular arc drawing, but a space curve fitted by using the cubic Bézier curve, which has better aerodynamic efficiency.

[0068] As Figure 4 shown, the theoretical formula of the cubic Bézier curve is:

[0069] B(t) = P0(1 - t) 3 + 3P1t(1 - t) 2 + 3P2t 2 (1 - t) + P3t 3 , t = (0 ~ 1);

[0070] In the formula: B(t) is the point at time t, P0 is the starting point in the same plane, P3 is the ending point, and P1 and P2 are the control points.

[0071] The continuous points Q0 from P0 to P1 describe a line segment; the continuous points Q2 from P1 to P2 describe a line segment; the continuous points Q4 from P2 to P3 describe a line segment; and the continuous points Q1 on the line from Q0 to Q2 describe a line segment; similarly, the continuous points Q1 on the line from Q2 to Q3 describe a line segment; the continuous points B(t) from Q1 to Q3 describe a cubic Bézier curve.

[0072] As Figures 5-7 shown, in order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, and the difference lies in that the angle β1 between the leading edge of the blade 12 closest to the hub surface of the impeller and the circumferential tangential direction is between 45 and 47 degrees;

[0073] the angle β1' between the leading edge of the outermost blade 12 and the circumferential tangential direction is between 23 and 25 degrees;

[0074] the angle β2 between the trailing edge of the blade 12 closest to the hub surface of the impeller and the circumferential tangential direction is between 48 and 52 degrees;

[0075] the angle β2' between the trailing edge of the outermost blade 12 and the circumferential tangential direction is between 30 and 35 degrees;

[0076] The included angle between the straight line passing through the center of the impeller from the outermost point of the leading edge of the blade 12 and the straight line passing through the center of the impeller from the outermost point of the trailing edge of the blade 12 is the blade wrap angle θ of the blade 12, and the blade wrap angle θ of the blade 12 is between 88 and 92 degrees.

[0077] Adopting the above preferred scheme, the above five parameter factors actually define the spatial twisted shape of the impeller blade 12. The impeller flow passage is a spatially curved flow passage with a gradually expanding cross-sectional area. When the gas flows through the impeller flow passage, due to the gradual increase in area, the gas flow velocity becomes uneven, resulting in a vortex phenomenon. Through simulation calculation and flow field analysis, for the shape of the blade 12 fitted within this parameter range of this impeller, when the gas flows through the impeller blade 12, the gas separation phenomenon of the blade 12 is relatively small, reducing the vortex loss.

[0078] In order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, and the difference lies in that the included angle between the outer end profile line of the trailing edge of the blade 12 and the horizontal plane is the trailing edge bevel angle α of the blade 12, and the trailing edge bevel angle α of the blade 12 is between 3 and 5 degrees.

[0079] Adopting the above preferred scheme, it has better aerodynamic efficiency, and the trailing edge bevel angle α of the blade 12 effectively suppresses the trailing edge separation phenomenon when the gas flows out of the impeller.

[0080] In order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that the number of blades 12 is between 7 and 9. The performance of the fan is relatively stable within the above parameter range, and the fluctuation error of the aerodynamic efficiency is relatively small, about 1% - 2%.

[0081] As Figure 8 shown, on the other hand, the present invention also discloses a motor, including: a housing 2, a wind cover 3, a bracket 4, a rear cover plate 5, a stationary impeller 6, an iron core 7, a rotor 8, a PCB electronic control board 9, and the high-load three-dimensional flow impeller 1 disclosed in any of the above embodiments.

[0082] As Figure 9 shown, in order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that heat dissipation holes 10 are provided at a position on the inner ring of the housing 2 close to the iron core 7.

[0083] By adopting the above preferred scheme, better heat dissipation can be achieved, and the heat dissipation problem of the motor iron core 7 under high power (above 450W) can be improved. The heat dissipation holes 10 can be designed into an indirect opening structure to further increase the air inlet area and cool the heating temperature of the iron core 7. The temperature of the iron core 7 is reduced by about 8 - 10 degrees compared with that without openings under the same power.

[0084] Furthermore, the ratio of the opening area S3 of the housing 2 to its inner ring area S4 is between 0.08 and 0.1.

[0085] By adopting the above preferred scheme, the heat dissipation effect is better.

[0086] As Figure 10 shown, in order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that a plurality of inner ring support ribs 21 and outer ring support ribs 22 are provided at intervals on the inner wall of the housing 2, and the length L1 of the inner ring support ribs 21 is half of the length L2 of the outer ring support ribs 22.

[0087] By adopting the above preferred scheme, the aerodynamic noise and aerodynamic efficiency can be well balanced. Furthermore, the total number of the inner ring support ribs 21 and the outer ring support ribs 22 is between 16 and 18.

[0088] As Figure 11 shown, in order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that the shaft hole 13 is a stepped structure, a section away from the stationary impeller 6 is a clearance section L3, and a section close to the stationary impeller 6 is an interference section L4, and the ratio of L3 to L4 is between 0.5 and 0.6.

[0089] With the above preferred solution, the clearance section L3 is used to apply a highly viscous mixed glue to fix the impeller. The impeller and the rotor shaft adopt an interference fit method, eliminating the risk of the impeller detaching from the shaft during high-speed rotation, and ensuring stable reliability.

[0090] The above-mentioned multiple implementation manners can be realized in a cross-parallel manner.

[0091] According to the demand trend of the vacuum cleaner motor market, based on a small-sized motor, while considering its manufacturing process, motor reliability, etc., the present invention discloses a high-power, relatively low-speed, high-load three-dimensional flow impeller and its motor.

[0092] The motor has a small-sized structure (the maximum diameter does not exceed 46 mm). After testing, as Figures 12-16 shown, Figure 12 the streamline diagram of Figure 13 and 14 the vector diagram of

[0093] Figure 16 In Figure 16 shows the performance curve diagrams of the actual efficiency, vacuum degree, and effective power of the motor at different flow rates.

[0094] The rotational speed of the present invention at full open (50 orifice plates) under a high power of 550 W is 109,000 RPM, and its pneumatic efficiency can reach up to 51.5% (tested based on the European standard air performance test standard IEC60312), which is far lower than the rotational speed of motors with a diameter greater than 46 mm on the market under the same power (the rotational speed at full open orifice plates exceeds 120,000 RPM).

[0095] The high-load three-dimensional flow impeller and its motor of the present invention have the following beneficial effects:

[0096] 1) Without changing the volume and power of the motor, the rotational speed is reduced.

[0097] 2) Due to the reduction of the rotational speed, the requirements for the motor components are relatively reduced, and the production cost is correspondingly reduced.

[0098] 3) The reliability of the motor life test under high power is improved.

[0099] The above embodiments are only used to illustrate the technical concept and features of the present invention, and their purpose is to enable those of ordinary skill in the art to understand the content of the present invention and implement it. However, the protection scope of the present invention cannot be limited thereby. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A high-load three-dimensional flow impeller, comprising: An impeller body and a plurality of blades with the same shape arranged on the impeller body. The center of the impeller body has a shaft hole, and the plurality of blades are arranged in a spiral pattern centered on the axis of the impeller body. It is characterized in that the impeller body is frustum-shaped, and the diameter of the impeller body near its air inlet side is smaller than the diameter of the impeller body near its air outlet side; the cone apex angle ε of the impeller body is between 60 and 65 degrees; The ratio of the inlet area S1 to the outlet area S2 of the impeller body is between 1 and 1.3; S1 = (D2 2 * π / 4) - (D1 2 * π / 4); S2 = (D4 2 * π / 4) - (D3 2 * π / 4); Wherein, D1 is the diameter of the circle tangent to the hub surface of the impeller by the leading edge of the blade; D2 is the diameter of the circle tangent to the outermost line of the leading edge of the blade; D3 is the diameter of the circle tangent to the hub surface of the impeller by the trailing edge of the blade; D4 is the diameter of the circle tangent to the outermost line of the trailing edge of the blade; The number of the blades is between 7 and 9; The profile line K1 and the profile line K2 of each blade are both space curves fitted by a third-order Bessel curve; Wherein, the profile line K1 is the profile line tangent to the side of the blade near the hub surface of the impeller; The profile line K2 is the outermost profile line of the blade far from the hub surface of the impeller.

2. The high-load three-dimensional flow impeller according to claim 1, wherein, The angle β1 between the leading edge of the innermost blade near the hub surface of the impeller and the circumferential tangential direction is between 45 and 47 degrees; The angle β1' between the leading edge of the outermost blade and the circumferential tangential direction is between 23 and 25 degrees; The angle β2 between the trailing edge of the innermost blade near the hub surface of the impeller and the circumferential tangential direction is between 48 and 52 degrees; The angle β2' between the trailing edge of the outermost blade and the circumferential tangential direction is between 30 and 35 degrees; The included angle between the straight line passing through the center of the impeller by the outermost point of the leading edge of the blade and the straight line passing through the center of the impeller by the outermost point of the trailing edge of the blade is the blade wrap angle θ, and the blade wrap angle θ is between 88 and 92 degrees.

3. The high-load three-dimensional flow impeller according to claim 1, wherein, The included angle between the profile line at the outer end of the trailing edge of the blade and the horizontal plane is the trailing edge bevel angle α, and the trailing edge bevel angle α is between 3 and 5 degrees.

4. A motor, wherein, Comprising: A casing, a wind hood, a bracket, a rear cover plate, a stationary impeller, a stator, a rotor, a PCB electronic control board, an iron core, and a high-load three-dimensional flow impeller according to any one of claims 1-3.

5. The motor according to claim 4, wherein, Heat dissipation holes are provided at a position near the iron core on the inner ring of the casing.

6. The motor according to claim 5, wherein, The ratio of the opening area S3 of the casing to its inner ring area S4 is between 0.08 and 0.

1.

7. The motor according to claim 4, wherein, A plurality of inner ring support ribs and outer ring support ribs are provided at intervals on the inner wall of the casing, and the length L1 of the inner ring support ribs is half of the length L2 of the outer ring support ribs.

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