A DC fan structure with a large air volume impeller

Abstract

This utility model relates to the technical field of fan manufacturing, and more particularly to a DC fan structure with a large-volume impeller. It includes a fan housing, characterized in that: the fan housing comprises an upper housing and a lower housing that cooperate to form an air duct; an air outlet is provided at the connection between the upper and lower housings; multiple snap-fit ​​connectors and connecting through holes are provided at the mating point between the upper and lower housings; an impeller assembly is housed inside the fan housing; and a drive unit, which is driven and connected to the impeller assembly, is located inside the impeller assembly. The DC fan of this application uses the upper and lower housings to form a closed guiding air duct, with an air outlet at the connection, which concentrates and confines the airflow, reduces dispersed turbulence, and improves output efficiency; the snaps and through holes facilitate quick and stable assembly and prevent vibration-induced loosening; the impeller assembly has a built-in drive unit, shortening the transmission chain, reducing energy consumption, and increasing kinetic energy conversion.

Description

Technical Field

[0001] This utility model relates to the field of wind turbine manufacturing technology, and in particular to a DC wind turbine structure with a large air volume impeller. Background Technology

[0002] In modern industrial and civil applications, DC fans, as devices that rely on motors to drive impellers for gas transport, are widely used in electronic equipment cooling, air purification, HVAC, industrial ventilation, and various scenarios requiring directional and controllable airflow. With the increasing power density of equipment and the growing demands for airflow and quiet operation in various environments, the market has placed comprehensive requirements on DC fans: they must possess large airflow to meet rapid heat or air exchange needs, while maintaining a compact structure, stable operation, reasonable energy consumption, and long service life. Currently, many DC fans designed for large airflow suffer from problems such as inadequate duct layout, long and costly power transmission links between the impeller and drive unit, insufficient shell rigidity leading to deformation affecting airflow during high-speed operation, poor concentricity and support stability between components causing vibration and airflow fluctuations, and difficulties in balancing lightweight and high strength in materials and molding processes. These factors collectively limit the efficiency and reliability of the fan under large airflow conditions.

[0003] Chinese patent discloses a DC centrifugal fan (publication number: CN 217735789 U) including a housing with an air inlet and an air outlet extending outward. The air outlet has an air vent, and an air passage is formed between the air inlet and the air vent. A box is installed at the air outlet, and a rectifier is installed inside the box. The air outlet has a through hole one and a through hole two. Air can flow into the box through the through hole one and out through the through hole two. However, this type of DC fan generally suffers from problems such as easy dispersion of airflow in the duct, large power transmission loss, insufficient housing rigidity leading to deformation and air leakage, poor component concentricity and support stability causing vibration and airflow fluctuation, and difficulty in balancing lightweight and high strength in materials and molding. Therefore, a DC fan structure with a large airflow impeller is needed. Utility Model Content

[0004] The purpose of this invention is to solve the problems commonly found in existing DC fans with large air volume designs, such as easy dispersion of airflow in the duct, large power transmission loss, insufficient shell rigidity leading to deformation and air leakage, poor component concentricity and support stability causing vibration and air volume fluctuations, and difficulty in balancing lightweight and high strength in materials and molding. Therefore, this invention proposes a DC fan structure with a large air volume impeller.

[0005] The technical solution adopted by this utility model to solve its technical problem is as follows: This utility model discloses a DC fan structure with a large-volume impeller, comprising a fan housing. The fan housing comprises an upper housing and a lower housing that cooperate to form an air duct. An air outlet is provided at the connection between the upper and lower housings. Multiple snap-fit ​​connectors and connecting through holes are provided at the connection between the upper and lower housings. An impeller assembly is provided inside the fan housing, and a drive unit connected to the impeller assembly is provided inside the impeller assembly. The upper and lower housings cooperate to form an independent air duct, which can concentrate and guide the airflow driven by the impeller to the air outlet, avoiding airflow loss due to airflow dispersion and improving airflow efficiency. The air outlet is located at the connection of the housings, shortening the airflow path within the housing, reducing turbulence interference, and making the airflow output smoother. The combination of snap-fit ​​connectors and connecting through holes ensures the convenience of housing assembly (quick snap-fit ​​positioning) and enhances the stability of the housing connection through the auxiliary reinforcement of the through holes, preventing the housing from loosening or separating due to vibration during operation. The drive unit is directly integrated inside the wind turbine assembly, which shortens the power transmission path (eliminating the need for external couplings or long-distance transmission) and reduces energy loss during transmission (such as friction and clearance loss). This allows the power of the drive unit to be converted into the rotational kinetic energy of the wind turbine more efficiently, indirectly improving the wind turbine's air output capacity.

[0006] Preferably, the wind turbine assembly includes an annular wind turbine body, which is composed of a central fixed part, multiple blades evenly distributed circumferentially, and inner and outer rings surrounding the blades. The annular structure of the annular wind turbine body expands the radial coverage of the wind turbine (compared to traditional non-annular wind turbines), providing more space for blade distribution. This allows for the arrangement of more or wider blades within the same volume, thereby increasing the volume of air propelled by a single rotation and directly improving airflow. The circumferentially evenly distributed blade design ensures balanced airflow propulsion in all directions during wind turbine rotation, avoiding airflow turbulence caused by excessively strong or weak local airflow, ensuring the uniformity and stability of airflow output, and further optimizing the effective airflow.

[0007] Preferably, the central fixing part includes a central shaft housing, a motor housing, a magnet ring, and a rotating shaft arranged sequentially from the outside to the inside. The rotating shaft is concentrically and coaxially arranged with the magnet ring, motor housing, and central shaft housing. This multi-layered nested concentric and coaxial structure integrates the core components of the drive unit (motor housing, magnet ring) and the rotating components of the wind turbine (rotating shaft) on the same central axis. This avoids the extra space occupation caused by component misalignment in traditional structures, making the wind turbine body structure more compact, freeing up more radial distribution space for the blades, indirectly increasing the wind turbine's airflow area, and contributing to a larger air volume.

[0008] Preferably, the drive unit includes a stator coil assembly, which is fixed to the inner wall of the motor housing. The stator coil assembly includes a stator core, and a ball bearing is provided at the center of the inner wall of the stator core. A pagoda spring is provided at the bottom of the ball bearing, and a plastic washer and a retaining ring are provided at the top of the ball bearing where it mates with the rotating shaft. The ball bearing, the pagoda spring, and the stator core are concentrically and coaxially arranged with the rotating shaft. As the core supporting component of the shaft, the ball bearing significantly reduces the resistance to shaft rotation by replacing sliding friction with rolling friction. This allows the power of the drive unit to be transmitted to the impeller more efficiently (reducing energy loss), resulting in smoother impeller rotation and stronger airflow propulsion. The pre-tightening design at the bottom of the pagoda spring automatically compensates for axial clearance caused by temperature changes (such as thermal expansion during operation) or assembly errors, preventing rotational wobbling caused by shaft "looseness". The plastic gasket at the top buffers the direct hard contact between the shaft and the retaining ring, reducing frictional damage. The retaining ring restricts the axial movement of the shaft. The three components work together to form an "elastic constraint", ensuring the stability of shaft rotation, preventing airflow output fluctuations caused by wobbling, and maintaining a continuous and stable large air volume.

[0009] Preferably, the lower shell surface is provided with multiple radially distributed reinforcing ribs, which extend from the central region of the lower shell to the outer periphery. The radially distributed reinforcing ribs extend from the center to the outer periphery, forming a "radial" support structure, which can effectively enhance the overall rigidity of the lower shell (especially when the wind turbine rotates at high speed and generates large wind pressure, the lower shell is easily deformed by the airflow reaction force); if the shell does not deform, the shape of the air duct (such as cross-sectional size and direction) remains stable, avoiding airflow blockage caused by narrow or twisted air ducts, and ensuring smooth passage of large air volumes.

[0010] Preferably, both the upper and lower housings are integrally injection molded from lightweight, high-strength engineering plastics. The use of lightweight engineering plastics reduces the overall weight of the unit, facilitating installation and use of the fan in confined spaces or in scenarios requiring lightweight design (such as portable devices and compact cooling systems). It also reduces the load on the drive unit (lighter weight means lower rotational inertia, making driving easier). The integral injection molding process eliminates seams in the housing (except for the designed air outlet and connection points), avoiding the accumulation of assembly errors caused by assembling multiple components (such as air leakage due to misaligned seams). It also improves the housing's sealing and structural integrity, further enhancing the stability of the airflow output.

[0011] The advantages of this utility model are: The DC fan structure provided by this utility model forms a closed and clearly oriented air duct through the cooperation of the upper and lower shells, and an air outlet is set at the connection between the two, so that the airflow driven by the impeller can be concentrated and constrained and smoothly discharged, reducing the dispersion and turbulence of the airflow within the shell, thereby improving the concentration and utilization efficiency of the airflow output. The snap-fit ​​connectors and connecting through holes set at the shell mating positions enable quick positioning and secure locking during the assembly process, preventing loosening due to vibration during operation from affecting the structural integrity and airflow path. The impeller assembly and the drive unit connected to the internal transmission within the fan shell allow power to be transmitted directly within the impeller, shortening the transmission chain length, reducing energy loss and response delay in intermediate links, and allowing the driving energy to be more fully converted into the rotational kinetic energy of the impeller. The annular impeller body of the impeller assembly, with the help of a central fixed part, circumferentially evenly distributed multiple blades, and inner and outer rings surrounding the blades, expands the radial air passage area and balances the airflow thrust in all directions. At the same time, the inner and outer rings constrain the airflow path, reduce airflow interference between blades, and allow more air to be pushed in a single rotation while maintaining uniform output. The central fixing section employs a concentric and coaxial design, consisting of a central shaft housing, motor housing, magnet ring, and rotating shaft arranged sequentially from the outside in. This design not only compactly accommodates the drive components and frees up more space for the blades, but also ensures that the center of gravity coincides with the axis during rotation, significantly reducing centrifugal offset and vibration. This maintains stable and high-speed operation of the impeller and prevents airflow turbulence or volume reduction due to vibration. The stator coil assembly of the drive unit is fixed to the inner wall of the motor housing. The ball bearings within the stator core provide elastic support through a bottom pagoda spring and a top plastic gasket and retaining ring. This automatically compensates for axial and radial deviations of the rotating shaft caused by thermal expansion or assembly errors, reducing rotational resistance and component wear. The concentric and coaxial layout ensures even force distribution and smooth operation, guaranteeing a continuous and stable power transmission to the impeller. Radial reinforcing ribs on the lower housing surface extend from the center outwards, enhancing the rigidity of the housing under wind pressure and vibration. This prevents housing deformation from causing narrowing or leakage in the air duct, maintaining a stable airflow channel and facilitating continuous high-volume airflow. Both the upper and lower housings are made of lightweight, high-strength engineering plastics through one-piece injection molding, which reduces the overall weight of the machine to facilitate installation and reduce the drive load. At the same time, the high strength of the material resists the impact and deformation during operation. The one-piece molding eliminates gaps and assembly errors caused by splicing multiple parts, improves the sealing performance and structural integrity of the housing, avoids air leakage, and maintains the integrity of the air duct. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of 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 only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram of the structure of this utility model.

[0014] Figure 2 This is a schematic diagram of the wind turbine assembly structure of this utility model.

[0015] Figure 3 This utility model Figure 2 A magnified view of A in the middle.

[0016] Figure 4 This is a schematic diagram of the structure of this utility model from another perspective.

[0017] In the diagram: 1. Air outlet; 2. Clip-on connector; 3. Lower housing; 4. Connecting through hole; 5. Upper housing; 6. Impeller assembly; 7. Outer ring; 8. Blade; 9. Inner ring; 10. Central shaft housing; 11. Motor housing; 12. Magnet ring; 13. Ball bearing; 14. Retaining ring; 15. Plastic gasket; 16. Rotating shaft; 17. Reinforcing rib. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model. Example

[0019] Please see Figure 1-4As shown, a DC fan structure with a large-volume impeller includes a fan housing. The fan housing comprises an upper housing 5 and a lower housing 3 that cooperate to form an air duct. An air outlet 1 is provided at the connection between the upper housing 5 and the lower housing 3. Multiple snap-fit ​​connectors 2 and connecting through holes 4 are provided at the connection between the upper housing 5 and the lower housing 3. An impeller assembly 6 is located inside the fan housing, and a drive unit that is connected to the impeller assembly 6 is located inside the impeller assembly 6. The upper housing 5 and the lower housing 3 cooperate to form an independent air duct, which can concentrate and guide the airflow driven by the impeller to the air outlet 1, avoiding airflow loss caused by airflow dispersion and improving airflow efficiency. The air outlet 1 is located at the connection of the housing, shortening the airflow path within the housing, reducing turbulence interference, and making the airflow output smoother. The combination of snap-fit ​​connectors 2 and connecting through holes 4 ensures convenient housing assembly (quick snap-fit ​​positioning) and enhances the stability of the housing connection through the reinforcement of the through holes, preventing the housing from loosening or separating due to vibration during operation. The drive unit is directly integrated inside the wind turbine assembly 6, which shortens the power transmission path (eliminating the need for external couplings or long-distance transmission), reduces energy loss during transmission (such as friction and gap loss), and enables the power of the drive unit to be converted into the rotational kinetic energy of the wind turbine more efficiently, thereby indirectly improving the wind turbine's air output capacity.

[0020] In this embodiment, the wind turbine assembly 6 includes an annular wind turbine body, which consists of a central fixed part, multiple blades 8 evenly distributed circumferentially, and an inner ring 9 and an outer ring 7 surrounding the blades 8. The annular structure of the annular wind turbine body expands the radial coverage range of the wind turbine (compared to traditional non-annular wind turbines), making the distribution space of the blades 8 more abundant. More or wider blades 8 can be arranged in the same volume, thereby increasing the volume of air pushed by a single rotation and directly improving the airflow. The design of the blades 8 being evenly distributed circumferentially ensures that the airflow driving force in all directions is balanced when the wind turbine rotates, avoiding airflow turbulence caused by excessively strong or weak local airflow, ensuring the uniformity and stability of airflow output, and further optimizing the effective airflow.

[0021] In this embodiment, the central fixing part includes a central shaft housing 10, a motor housing 11, a magnet ring 12, and a rotating shaft 16 arranged sequentially from the outside to the inside. The rotating shaft 16 is concentrically and coaxially arranged with the magnet ring 12, the motor housing 11, and the central shaft housing 10. The multi-layered nested concentric and coaxial structure integrates the core components of the drive unit (motor housing 11 and magnet ring 12) and the rotating components of the wind turbine (rotating shaft 16) on the same central axis. This avoids the extra space occupation caused by component misalignment in traditional structures, making the structure of the wind turbine body more compact, freeing up more radial distribution space for the blades 8, indirectly increasing the wind turbine's air passage area, and contributing to a large air volume.

[0022] In this embodiment, the drive unit includes a stator coil assembly, which is fixed to the inner wall of the motor housing 11. The stator coil assembly includes a stator core, and a ball bearing 13 is provided at the center of the inner wall of the stator core. A pagoda spring is provided at the bottom of the ball bearing 13. A plastic gasket 15 and a retaining ring 14 are provided at the top of the ball bearing 13 where it mates with the rotating shaft 16. The ball bearing 13, the pagoda spring, and the stator core are concentrically and coaxially arranged with the rotating shaft 16. As the core supporting component of the rotating shaft 16, the ball bearing 13 significantly reduces the resistance to rotation of the rotating shaft 16 by replacing sliding friction with rolling friction. This allows the power of the drive unit to be transmitted to the impeller more efficiently (reducing energy loss), making the impeller rotate more smoothly and the airflow propulsion capacity stronger. The pre-tightening design at the bottom of the pagoda spring can automatically offset the axial clearance of the rotating shaft 16 caused by temperature changes (such as thermal expansion during operation) or assembly errors, preventing rotational wobbling caused by the "looseness" of the rotating shaft 16. The plastic gasket 15 at the top can buffer the direct hard contact between the rotating shaft 16 and the retaining ring 14, reducing frictional damage. The retaining ring 14 restricts the axial movement of the rotating shaft 16. The three components work together to form an "elastic constraint," ensuring the stability of the rotation of the rotating shaft 16, avoiding airflow output fluctuations caused by wobbling, and maintaining a continuous and stable large air volume.

[0023] In this embodiment, the surface of the lower housing 3 is provided with a plurality of radially distributed reinforcing ribs 17, which extend from the central region of the lower housing 3 to the outer periphery. The radially distributed reinforcing ribs 17 extend from the center to the outer periphery, forming a "radial" support structure, which can effectively enhance the overall rigidity of the lower housing 3 (especially when the wind turbine rotates at high speed and generates large wind pressure, the lower housing 3 is easily deformed by the airflow reaction force); if the housing does not deform, the shape of the air duct (such as cross-sectional size and direction) remains stable, avoiding airflow blockage caused by narrow or twisted air ducts, and ensuring smooth passage of large airflow.

[0024] In this embodiment, both the upper shell 5 and the lower shell 3 are integrally injection molded from lightweight, high-strength engineering plastics; or, the upper shell 5 and the lower shell 3 are structurally a single shell integrally molded, with the air duct and air outlet directly formed inside, eliminating the need for separate assembly and improving structural integrity and sealing; or, after assembly, the two sides of the upper shell 5 and the lower shell 3 form an integral through structure, creating dual air inlets that allow airflow to enter from both sides of the impeller, enabling the impeller to simultaneously draw in air from both sides and discharge it through the air duct and outlet during operation, thereby increasing the air intake area. Improved airflow uniformity and increased air volume; the application of lightweight engineering plastics reduces the overall weight of the unit, making it easier to install and use the fan in confined spaces or in scenarios requiring lightweight design (such as portable devices and compact cooling systems), while also reducing the load on the drive unit (lighter weight means less rotational inertia, making drive easier); the one-piece injection molding process eliminates gaps in the housing (except for the designed air outlet 1 and connection position), avoiding the accumulation of assembly errors caused by the assembly of multiple parts (such as air leakage caused by misaligned seams), while also improving the sealing and structural integrity of the housing, further enhancing the stability of air volume output.

[0025] The implementation principle of this embodiment is as follows: The fan casing is composed of an upper casing 5 and a lower casing 3 that fit together to form a closed air duct. An air outlet 1 is located at the connection between the upper casing 5 and the lower casing 3 to concentrate and discharge the airflow at the end of the air duct. Multiple snap-fit ​​connectors 2 and connecting through holes 4 are also provided at the mating points of the upper casing 5 and the lower casing 3. During assembly, the snap-fit ​​connectors quickly position the casing, and the connecting through holes 4 assist in locking it in place, ensuring the casing forms a stable and sealed whole, preventing loosening due to vibration during operation and ensuring the integrity of the air duct. The surface of the lower casing 3 has multiple radially distributed reinforcing ribs 17. These ribs 17 extend from the center of the lower casing 3 outwards, resisting deformation caused by wind pressure and vibration during subsequent operation and maintaining the stability of the air duct shape. Both the upper casing 5 and the lower casing 3 are integrally injection molded from lightweight, high-strength engineering plastics, giving the entire unit both lightweight and sufficient rigidity. The integral molding eliminates seams, improving sealing and reducing air leakage.

[0026] The fan housing houses a rotor assembly 6, which in turn houses a drive unit that is connected to the rotor assembly 6 for transmission. The core of the drive unit is the stator coil assembly, which is fixed to the inner wall of the motor housing 11 and contains the stator core. A ball bearing 13 is installed at the center of the inner wall of the stator core. A pagoda spring is provided at the bottom of the ball bearing 13 to provide axial preload, and a plastic gasket 15 is provided at the top where it mates with the shaft 16 to buffer friction and a retaining ring 14 is added to limit axial displacement. The ball bearing 13, pagoda spring, stator core, and shaft 16 are concentrically and coaxially arranged. This reduces the rotational resistance of the shaft 16 and automatically compensates for minor misalignments caused by temperature rise or assembly errors through elastic support, ensuring smooth and stable operation of the shaft 16.

[0027] The wind turbine assembly 6 includes an annular wind turbine body, which consists of a central fixed part, multiple blades 8 evenly distributed around the circumference, and an inner ring 9 and an outer ring 7 surrounding the blades 8. The central fixed part is arranged sequentially from the outside to the inside, including a central shaft housing 10, a motor housing 11, a magnet ring 12, and a rotating shaft 16, with the rotating shaft 16 concentrically and coaxially arranged with the magnet ring 12, the motor housing 11, and the central shaft housing 10. When the stator coil assembly of the drive unit is energized, the stator core generates a rotating magnetic field, which acts on the magnet ring 12 fixed on the rotating shaft 16, forming an electromagnetic torque that drives the rotating shaft 16 to rotate around its axis. When the rotating shaft 16 rotates, it directly drives the concentric central fixed part to rotate, thereby causing the entire annular wind turbine body to rotate accordingly.

[0028] Multiple blades 8, evenly distributed circumferentially, rotate synchronously with the central fixed part of the annular impeller body, continuously pushing air from the inner ring 9 to the outer side during rotation. The inner ring 9 and outer ring 7 surround the blades 8, providing installation boundaries for the blades 8 and constraining the airflow along the annular channel, reducing mutual interference between the airflows of the blades 8 (such as eddies and backflow), allowing the airflow to converge more concentratedly and smoothly towards the outer ring 7 under the push of the blades 8, forming a high-speed airflow cluster. The multi-layered concentric and coaxial structure of the central fixed part not only compactly accommodates the drive components but also provides more radial distribution space for the blades 8, increasing the volume of air pushed in a single rotation, thereby improving the airflow.

[0029] The air duct formed by the upper shell 5 and the lower shell 3 receives the airflow pushed out by the impeller body. The duct wall restricts the airflow from spreading and guides it to the air outlet 1 at the shell connection. Since the air outlet 1 is located at the shell connection, the airflow path inside the shell is shorter, reducing turbulence and energy loss, so that the airflow is concentrated and discharged at the air outlet 1, forming a directional large air volume output.

[0030] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," 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 the present invention. 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.

[0031] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A DC fan structure with a large air volume impeller, comprising a fan housing, characterized in that: The fan housing includes an upper housing (5) and a lower housing (3) that cooperate to form an air duct. An air outlet (1) is provided at the connection between the upper housing (5) and the lower housing (3). Multiple snap-fit ​​connectors (2) and connecting through holes (4) are provided at the connection between the upper housing (5) and the lower housing (3). A wind turbine assembly (6) is provided inside the fan housing. A drive unit that is connected to the wind turbine assembly (6) is provided inside the wind turbine assembly (6).

2. The DC fan structure with a large air volume impeller according to claim 1, characterized in that: The wind turbine assembly (6) includes an annular wind turbine body, which is composed of a central fixed part, a plurality of blades (8) evenly distributed around the circumference, and an inner ring (9) and an outer ring (7) surrounding the blades (8).

3. The DC fan structure with a large air volume impeller according to claim 2, characterized in that: The central fixing part includes a central shaft housing (10), a motor housing (11), a magnet ring (12) and a rotating shaft (16) arranged sequentially from the outside to the inside. The rotating shaft (16) is coaxially arranged with the magnet ring (12), the motor housing (11) and the central shaft housing (10).

4. The DC fan structure with a large air volume impeller according to claim 3, characterized in that: The drive unit includes a stator coil assembly, which is fixed to the inner wall of the motor housing (11). The stator coil assembly includes a stator core, and a ball bearing (13) is provided at the center of the inner wall of the stator core. A pagoda spring is provided at the bottom of the ball bearing (13). A plastic gasket (15) and a retaining ring (14) are provided at the top of the ball bearing (13) where it mates with the rotating shaft (16). The ball bearing (13), the pagoda spring, and the stator core are concentrically and coaxially arranged with the rotating shaft (16).

5. The DC fan structure with a large air volume impeller according to claim 1, characterized in that: The lower shell (3) has a plurality of radially distributed reinforcing ribs (17) on its surface, the reinforcing ribs (17) extending from the central region of the lower shell (3) to the outer periphery.

6. The DC fan structure with a large air volume impeller according to claim 1, characterized in that: Both the upper shell (5) and the lower shell (3) are integrally injection molded from lightweight, high-strength engineering plastics.

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