Forward multi-wing centrifugal impeller and centrifugal fan

Abstract

The utility model relates to centrifugal impeller field provides a forward multi -wing centrifugal impeller and centrifugal fan, and centrifugal impeller includes: front disc, back disc, a plurality of blades, a plurality of blades are fixed between front disc and back disc and along the equal interval arrangement of impeller circumference, driving part, back disc installs in driving part, and driving part is used for driving the rotation of the impeller group formed by front disc, a plurality of blades and back disc, the blade has inner end and outer end, and inner end is close to impeller center setting, and outer end is away from impeller center setting, and the blade arcs from inner end to outer end and extends, and the blade entry angle formed in inner end is 70~75 DEG, and the blade exit angle formed in outer end is 170~180 DEG. The utility model is used to solve the defect that fan static pressure and efficiency decline due to the impeller air intake space is sheltered in the prior art, improves airflow flow performance through optimizing blade angle parameter, improves fan static pressure and efficiency.

Description

Technical Field

[0001] This utility model relates to the field of centrifugal impeller technology, and in particular to a forward-curving multi-blade centrifugal impeller and a centrifugal fan. Background Technology

[0002] Forward-curved centrifugal fans, with their advantages of compact structure, large flow coefficient, and adaptability to low air pressure conditions, have become core components in household and commercial air conditioning and ventilation equipment. A typical structure includes a collector, a forward-curved centrifugal impeller, a volute, and a drive motor. During operation, external gas, under the negative pressure created by the impeller's rotation, is guided axially into the impeller's interior by the collector. The high-speed rotating impeller applies centrifugal force to the airflow through its multi-bladed design, converting the mechanical energy input from the motor into the kinetic and pressure energy of the airflow. This causes the airflow to accelerate radially outward within the blade channels, increasing its pressure. Finally, the high-pressure, high-speed airflow exits from the impeller's outer circumference outlet and enters the annular cavity of the volute. The volute, through channels with gradually changing cross-sectional areas, decelerates and pressurizes the airflow, which is then delivered to subsequent airflow paths through the volute's outlet to complete the ventilation or heat exchange function.

[0003] In order to reduce the overall size of the fan, existing technologies have optimized the types of drive components and the installation method of the drive components and impeller. However, this has the problem of obstructing the air intake space of the impeller, which leads to a decrease in the static pressure and efficiency of the fan. Utility Model Content

[0004] This invention provides a forward-curved multi-blade centrifugal impeller and a centrifugal fan to solve the defects in the prior art where the fan static pressure and efficiency decrease due to the obstruction of the impeller air inlet space. By optimizing the blade angle parameters, the airflow performance is improved, thereby increasing the fan static pressure and efficiency.

[0005] This utility model provides a forward-curving multi-blade centrifugal impeller, comprising: Front board; Backboard; Multiple blades, the multiple blades being fixed between the front disk and the rear disk and arranged at equal intervals along the circumference of the impeller; A drive unit, wherein the rear disc is mounted on the drive unit, and the drive unit is used to drive the impeller assembly formed by the front disc, the plurality of blades and the rear disc to rotate; The blade has an inner end and an outer end. The inner end is located near the center of the impeller, and the outer end is located away from the center of the impeller. The blade extends in an arc from the inner end to the outer end. The blade inlet angle formed at the inner end is 70° to 75°, and the blade outlet angle formed at the outer end is 170° to 180°.

[0006] According to the present invention, a forward-curving multi-blade centrifugal impeller has an inner diameter of D1 and an outer diameter of D2, with the ratio of D1 to D2 being 0.8-0.85.

[0007] According to the present invention, a forward-curving multi-blade centrifugal impeller is provided, wherein the rear disc includes an annular mounting plate and a conical sleeve disposed on the inner circumference of the mounting plate, and the driving component is partially nested inside the conical sleeve.

[0008] According to the present invention, a forward multi-blade centrifugal impeller is provided, wherein the driving component is an external rotor motor, including a rotor and a rotor housing disposed outside the rotor, and the conical sleeve is interference-fitted with the rotor housing.

[0009] According to the present invention, a forward-curving multi-blade centrifugal impeller is provided, wherein the conical sleeve includes a first conical portion extending obliquely toward one side of the blade, a first annular portion connected to the inner end of the first conical portion, and a mounting portion extending from the inner end of the first annular portion toward the blade. The rotor housing includes a second tapered portion adapted to the first tapered portion, a second annular portion adapted to the first annular portion, and a mating portion adapted to the mounting portion.

[0010] According to the present invention, a forward multi-blade centrifugal impeller is provided, wherein a limiting structure is provided between the first annular portion and the second annular portion; And / or, a limiting structure is provided between the mounting part and the mating part.

[0011] According to the present invention, a forward-curving multi-blade centrifugal impeller is provided, wherein the mounting plate is provided with a plurality of spaced first slots along the circumferential direction, and the blades are provided with a first lug at one end facing the mounting plate, which is inserted into and cooperates with the first slot.

[0012] According to the present invention, a forward-curving multi-blade centrifugal impeller is provided, wherein the front disc is provided with a plurality of spaced second slots along the circumferential direction, and the blades are provided with a second lug at one end facing the front disc, which is engaged with the second slot.

[0013] According to the present invention, a forward-curving multi-blade centrifugal impeller is provided, wherein the first lug and the second lug are disposed in the middle of the line connecting the inner end and the outer end.

[0014] This utility model also provides a centrifugal fan, including the forward multi-blade centrifugal impeller as described above.

[0015] The forward-curved multi-blade centrifugal impeller and centrifugal fan provided by this invention solve the problems of static pressure drop and efficiency reduction caused by the obstruction of the air intake space by the drive component by optimizing the blade inlet and outlet angle parameters. The blade inlet angle is 70°–75°. Increasing the inlet angle allows for a more stable adhering flow at the blade leading edge, reducing local turbulence intensity. The increased inlet angle also enhances the guiding ability of the airflow at the inner end of the blade, weakening the lateral airflow deviation caused by the obstruction component. This makes the airflow velocity vector entering the blade channel closer to the axial direction, reducing energy dissipation due to velocity gradients. The blade outlet angle is 170°–180°, which strengthens centrifugal pressurization and improves static pressure conversion efficiency. Through the matching of the inlet and outlet angles, a stabilizing flow followed by pressurization effect can be achieved. The synergistic effect of the inlet and outlet angles reduces the axial velocity gradient of the airflow within the blade channel, weakening the secondary flow caused by the obstruction of the drive component. This results in a more uniform pressure distribution of the airflow within the blade channel, reducing structural resonance caused by airflow pulsation and thus reducing noise. By optimizing aerodynamic parameters, static pressure output can be increased, eddy current and secondary flow losses can be suppressed, static pressure efficiency can be improved, equipment operating energy consumption can be reduced, airflow smoothness can be improved, thereby reducing noise and improving user experience, all without increasing the size of the fan. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is one of the structural schematic diagrams of the forward-curving multi-blade centrifugal impeller provided by this utility model; Figure 2 This is the second schematic diagram of the forward-curving multi-blade centrifugal impeller provided by this utility model; Figure 3 This is an exploded view of the forward-curving multi-blade centrifugal impeller provided by this utility model; Figure 4 This is a schematic diagram of the blade distribution provided by this utility model.

[0018] Figure 5 yes Figure 4 A magnified schematic diagram of the blade at point A.

[0019] Figure label: 10. Front plate; 101. Second slot; 11. Rear plate; 12. Blade; 121. Inner end; 122. Outer end; 123. First lug; 124. Second lug; 13. Mounting plate; 131. First slot; 14. Conical sleeve; 141. First conical part; 142. First annular part; 143. Mounting part; 15. Outer rotor motor; 151. Second conical part; 152. Second annular part; 153. Mating part. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] In the description of this utility model, it should be understood that the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0022] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0023] In this utility model, unless otherwise expressly specified and limited, the first feature "on" or "below" the second feature may be in direct contact with the first and second features, or indirect contact through an intermediate medium. In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0024] like Figures 1 to 5 As shown, this utility model provides a forward-curving multi-blade centrifugal impeller, comprising: 10 in the front row; 11 in the backcourt; Multiple blades 12 are fixed between the front disk 10 and the rear disk 11 and are arranged at equal intervals along the circumference of the impeller. A drive unit, wherein the rear disc 11 is mounted on the drive unit, and the drive unit is used to drive the impeller assembly formed by the front disc 10, the plurality of blades 12 and the rear disc 11 to rotate; The blade 12 has an inner end 121 and an outer end 122. The inner end 121 is located close to the center of the impeller, and the outer end 122 is located away from the center of the impeller. The blade 12 extends arcuately from the inner end 121 to the outer end 122. The inlet angle of the blade 12 formed at the inner end 121 is 70° to 75°, and the outlet angle of the blade 12 formed at the outer end 122 is 170° to 180°.

[0025] like Figures 1 to 3 As shown, the front disc 10, blades 12, rear disc 11, and drive components are connected sequentially. To reduce the fan size, the drive component can be, for example, an external rotor motor 15, with the rotor directly enclosing the stator for rotation. The rear disc 11 is rigidly connected to the outer wall of the rotor of the external rotor motor 15, eliminating the traditional drive shaft structure of an internal rotor motor. This significantly shortens the axial dimension of the fan, meeting the design requirements for compactness. Since the drive components are directly connected to the impeller rear disc 11 and rotate coaxially, they inevitably end up in the rear end region of the impeller, and some components extend towards the air inlet of the impeller front disc 10. This results in the axial air inlet space of the impeller being squeezed or blocked. The obstruction of the air inlet space has a significant negative impact on the static pressure output and operating efficiency of the fan. This invention provides a new approach to optimizing the performance of centrifugal fans by optimizing the aerodynamic parameters of the blades 12.

[0026] like Figure 4 and Figure 5As shown, the inner ends 121 of multiple blades 12 are connected circumferentially to form an inner circumference. The inlet angle α of the blade 12 is the angle between the tangent of the inner circumference and the tangent of the arc surface of the inner end 121 of the blade 12. The outer ends 122 of multiple blades 12 are connected circumferentially to form an outer circumference. The outlet angle β of the blade 12 is the angle between the tangent of the outer circumference and the tangent of the arc surface of the outer end 122 of the blade 12. By optimizing the inlet angle α of the blade 12, airflow turbulence can be suppressed and intake smoothness can be improved. The specific value of the inlet angle α of the blade 12 can be, for example, 70°, 71°, 72°, 73°, 74°, 75°, etc., set according to actual needs. By optimizing the outlet angle β of the blade 12, when the airflow leaves the blade 12 at an outlet angle of 170° to 180°, the circumferential component of its absolute velocity increases significantly. After being diffused by the volute, more kinetic energy is converted into static pressure, thereby improving static pressure output. The specific value of the exit angle β of blade 12 can be, for example, 170°, 175°, 180°, etc., and can be set according to actual needs.

[0027] Furthermore, the impeller inner diameter is D1, the impeller outer diameter is D2, and the ratio of D1 to D2 is 0.8-0.85.

[0028] Here, the impeller inner diameter refers to the circumference diameter of the inner end 121 of blade 12, and the impeller outer diameter refers to the circumference diameter of the outer end 122 of blade 12. By limiting D1 / D2 to 0.8-0.85, the problem of excessively small inner diameter in traditional small-ratio impellers, resulting in a narrow flow cross-section in the central air intake area of ​​the impeller, requires the airflow to undergo a rapid contraction-turning process upon entry, easily forming vortices and airflow separation at the inner end 121 (inlet side) of blade 12, leading to significant inlet flow losses. When D1 / D2 is 0.8-0.85, on the one hand, D2 still maintains a sufficiently large outer diameter to ensure the strength of the centrifugal force generated when the impeller rotates; on the other hand, the increase in D1 ensures that the airflow has a certain initial radial velocity when entering the impeller, making the radial acceleration process of the airflow between blades 12 more efficient, ultimately converting into a higher static pressure value, compensating for the static pressure loss caused by the outer rotor motor 15 obstructing the air intake space.

[0029] In a preferred embodiment of the present invention, the rear plate 11 includes an annular mounting plate 13 and a conical sleeve 14 disposed on the inner periphery of the mounting plate 13, and the driving component is partially nested inside the conical sleeve 14.

[0030] like Figure 3As shown, the rear plate 11 forms a conical sleeve 14 that protrudes towards the blade 12. The drive component is fitted inside the conical sleeve 14, which can significantly reduce the overall axial dimension of the impeller, achieving miniaturization and compactness of the fan structure. The conical sleeve 14 also facilitates the guiding installation of the drive component. The guiding effect of the conical surface automatically corrects the axial misalignment between the drive component and the impeller, forcing their rotational axes to coincide, improving coaxiality, enhancing rotational stability, and reducing high-frequency noise caused by vibration.

[0031] In some embodiments, the drive component is an external rotor motor 15, which includes a rotor and a rotor housing disposed outside the rotor, and the tapered sleeve 14 is interference-fitted with the rotor housing.

[0032] By using an interference fit between the tapered sleeve 14 and the rotor housing, a continuous radial clamping force is generated through the elastic deformation of the assembled components. This allows the rear disc 11 to form an integrated rigid connection with the motor rotor housing, improving assembly stability and reliability, avoiding the risk of loosening during operation, dispersing stress concentration during impeller rotation (such as the localized stress in traditional bolted connections), reducing the risk of fatigue damage at the connection between the rear disc 11 and the motor, and extending the overall structural lifespan. The rigid connection formed by the interference fit prevents coaxiality misalignment caused by impeller vibration during rotation, ensuring the impeller always rotates stably around the motor shaft. This makes the gas flow path from the collector inlet to the volute outlet smoother, reducing eddy current losses and further optimizing the blade angle of the blade 12, maximizing fan performance. Furthermore, the interference fit assembly method is simple to operate, eliminating the need for complex bolt tightening or calibration procedures, reducing production and assembly costs, and preventing the risk of bolts and other parts falling off during high-speed rotation, thus improving structural safety.

[0033] Furthermore, the conical sleeve 14 includes a first conical portion 141 extending obliquely toward the blade 12, a first annular portion 142 connected to the inner end 121 of the first conical portion 141, and a mounting portion 143 extending from the inner end 121 of the first annular portion 142 toward the blade 12; the rotor housing includes a second conical portion 151 adapted to the first conical portion 141, a second annular portion 152 adapted to the first annular portion 142, and a mating portion 153 adapted to the mounting portion 143.

[0034] like Figure 3 As shown, during specific installation, the rotor housing extends into the opening of the conical sleeve 14, the conical surface of the second conical part 151 fits against the conical surface of the first conical part 141, the first annular part 142 abuts against the second annular part 152, and the mounting part 143 is fitted onto the mating part 153. Through interference fit, the motor and the rear plate 11 are coaxially and securely installed, which improves the axial compactness of the impeller, ensures the installation firmness, and ensures the reliability of synchronous rotation.

[0035] Furthermore, in order to enhance the synchronous rotation performance of the conical sleeve 14 and the motor, a limiting structure is provided between the first annular portion 142 and the second annular portion 152. The limiting structure is, for example, a matching structure of a limiting protrusion and a limiting groove. The specific form is set according to actual needs, and this utility model does not make any requirements.

[0036] It is understood that the limiting structure can also be provided between the mounting part 143 and the mating part 153, or the limiting structure can be provided in multiple places, with limiting structures provided between the first annular part 142 and the second annular part 152, and between the mounting part 143 and the mating part 153.

[0037] Furthermore, the mounting plate 13 is provided with a plurality of spaced first slots 131 along the circumferential direction, and the blade 12 is provided with a first lug 123 at one end facing the mounting plate 13, which is inserted into and cooperates with the first slots 131.

[0038] The impeller is installed by inserting the first lug 123 into the first slot 131. The structure is simple, the fixation is reliable, and it is also beneficial to reduce the axial dimension of the impeller.

[0039] Furthermore, the front disc 10 is provided with a plurality of spaced second slots 101 along the circumferential direction, and the blade 12 is provided with a second lug 124 at one end facing the front disc 10, which is engaged with the second slots 101.

[0040] The impeller is installed by inserting the second lug 124 into the second slot 101. The structure is simple and secure, and it helps to reduce the axial dimension of the impeller. The number of blades 12, first slots 131 and second slots 101 are the same, with each blade 12 corresponding to one first slot 131 and one second slot 101.

[0041] Furthermore, the first lug 123 and the second lug 124 are disposed in the middle of the line connecting the inner end 121 and the outer end 122.

[0042] By placing the first lug 123 and the second lug 124 at the middle position in the width direction of the blade 12, the stress distribution of the blade 12 can be optimized, avoiding deformation or breakage under high-speed rotation and improving structural durability. At the same time, it can improve the assembly reliability of the blade 12 with the front disk 10 and the rear disk 11, ensuring the rigidity of the impeller assembly structure.

[0043] This utility model also provides a centrifugal fan, including the forward multi-blade centrifugal impeller of the above embodiments and examples, which has all the beneficial effects of the above embodiments and examples, and will not be repeated here.

[0044] Centrifugal fans may also include a volute, where the impeller draws air into the volute's collecting chamber. The airflow then flows along the internal duct of the volute and is finally discharged from the outlet. Based on the impeller improvements described above, centrifugal fans can improve static pressure and efficiency while maintaining a compact structure.

[0045] The forward-curved multi-blade centrifugal impeller and centrifugal fan provided by this invention solve the problems of static pressure drop and efficiency reduction caused by the obstruction of the air intake space by the drive component by optimizing the inlet and outlet angle parameters of the blade 12. The inlet angle of the blade 12 is 70° to 75°. By increasing the inlet angle of the blade 12, a more stable attached flow can be formed at the leading edge of the blade 12, reducing the intensity of local turbulence. The increased inlet angle enhances the guiding ability of the airflow at the inner end 121 of the blade 12, weakens the lateral deviation of the airflow caused by the obstruction component, and makes the velocity vector of the airflow entering the blade 12 channel closer to the axial direction, reducing energy dissipation caused by velocity gradient. The outlet angle of the blade 12 is 170° to 180°, which can enhance centrifugal pressurization and improve static pressure conversion efficiency. By matching the inlet and outlet angles as described above, a stabilizing effect followed by pressurization can be achieved. The synergistic effect of the inlet and outlet angles reduces the axial velocity gradient of the airflow within the 12-channel blade, weakening the secondary flow caused by the obstruction of the drive components. This results in a more uniform pressure distribution of the airflow within the 12-channel blade, reducing structural resonance caused by airflow pulsation and thus reducing noise. Through aerodynamic parameter optimization, without increasing the fan size, static pressure output can be increased, eddy current and secondary flow losses can be suppressed, static pressure efficiency can be improved, equipment operating energy consumption can be reduced, and airflow smoothness can be improved, thereby reducing noise and improving the user experience.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A forward multi-wing centrifugal impeller characterized by, include: Front plate (10); Backboard (11); Multiple blades (12) are fixed between the front disc (10) and the rear disc (11) and are arranged at equal intervals along the circumference of the impeller; A drive unit, wherein the rear disc (11) is mounted on the drive unit, and the drive unit is used to drive the impeller assembly formed by the front disc (10), the plurality of blades (12) and the rear disc (11) to rotate; The blade (12) has an inner end (121) and an outer end (122). The inner end (121) is located close to the center of the impeller, and the outer end (122) is located away from the center of the impeller. The blade (12) extends arcuately from the inner end (121) to the outer end (122). The inlet angle of the blade (12) formed at the inner end (121) is 70° to 75°, and the outlet angle of the blade (12) formed at the outer end (122) is 170° to 180°.

2. The forward-curving multi-blade centrifugal impeller according to claim 1, characterized in that, The impeller inner diameter is D1, the impeller outer diameter is D2, and the ratio of D1 to D2 is 0.8-0.

85.

3. The forward-curving multi-blade centrifugal impeller according to claim 1, characterized in that, The rear plate (11) includes an annular mounting plate (13) and a conical sleeve (14) disposed on the inner periphery of the mounting plate (13), and the driving component is partially nested inside the conical sleeve (14).

4. The forward-curving multi-blade centrifugal impeller according to claim 3, characterized in that, The driving component is an external rotor motor (15), which includes a rotor and a rotor housing located outside the rotor. The tapered sleeve (14) is interference-fitted with the rotor housing.

5. The forward-curving multi-blade centrifugal impeller according to claim 4, characterized in that, The conical sleeve (14) includes a first conical portion (141) extending obliquely toward the blade (12), a first annular portion (142) connected to the inner end (121) of the first conical portion (141), and a mounting portion (143) extending from the inner end (121) of the first annular portion (142) toward the blade (12). The rotor housing includes a second tapered portion (151) adapted to the first tapered portion (141), a second annular portion (152) adapted to the first annular portion (142), and a mating portion (153) adapted to the mounting portion (143).

6. The forward-curving multi-blade centrifugal impeller according to claim 5, characterized in that, A limiting structure is provided between the first annular portion (142) and the second annular portion (152); And / or, a limiting structure is provided between the mounting part (143) and the mating part (153).

7. The forward-curving multi-blade centrifugal impeller according to claim 3, characterized in that, The mounting plate (13) has a plurality of spaced first slots (131) arranged circumferentially, and the blade (12) has a first lug (123) at one end facing the mounting plate (13) that engages with the first slot (131).

8. The forward-curving multi-blade centrifugal impeller according to claim 7, characterized in that, The front disc (10) is provided with a plurality of spaced second slots (101) along the circumferential direction, and the blade (12) is provided with a second lug (124) at one end facing the front disc (10) to engage with the second slots (101).

9. The forward-curving multi-blade centrifugal impeller according to claim 8, characterized in that, The first lug (123) and the second lug (124) are located in the middle of the line connecting the inner end (121) and the outer end (122).

10. A centrifugal fan characterized by Including the forward-curved multi-bladed centrifugal impeller as described in any one of claims 1 to 9.

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