A suspension type shaftless heat-dissipating fan and a control method thereof

Abstract

This application discloses a suspended shaftless cooling fan, comprising: suspended blades, each including a suspension cylinder and blades; a fan frame, the fan frame having an annular groove, and a magnetic levitation positioning magnet assembly and a magnetic levitation drive assembly disposed between the annular groove and the outer wall of the suspension cylinder; the magnetic levitation drive assembly including a rotor magnet ring and an electromagnetic drive coil winding; the magnetic levitation positioning magnet assembly including a first positioning magnet, a second positioning magnet, a first positioning winding, and a second positioning winding. This application also discloses a control method. This invention belongs to the field of electrical engineering and heat dissipation equipment technology. Besides addressing the friction loss, efficiency reduction, heat generation, and wear problems caused by mechanical contact, it significantly improves the product's service life, operating efficiency, and reliability. By using multiple sets of distance sensors to monitor the rotor position in real time, it ensures that the fan always starts from the optimal position, avoiding vibration caused by eccentric starting.

Description

Technical Field

[0001] This application relates to the fields of electrical engineering and heat dissipation equipment technology, and in particular to a suspended shaftless cooling fan and its control method. Background Technology

[0002] Traditional cooling fans typically rely on physical bearings (such as ball bearings or oil-impregnated bearings) to support and guide the rotor's rotation. This mechanical contact structure inevitably involves friction, leading to a series of problems: efficiency loss, mechanical noise, wear, and limited lifespan. These problems are particularly pronounced in high-speed or long-term continuous operation scenarios. In traditional cooling fans, the drive shaft and motor are both located at the center of rotation. The motor occupies a significant portion of the fan blade area, greatly reducing the airflow area and resulting in low cooling efficiency. Traditional cooling fans use ball bearings or self-lubricating bearings on their rotating shafts, and the bearings are the primary limiting factor for the fan's lifespan.

[0003] The emergence of brushless DC motors (BLDC) and magnetic levitation technology has partially solved these problems. The brushless design eliminates the friction and sparks caused by brushes, while magnetic levitation technology uses electromagnetic force to levitate the rotor, achieving contactless operation and fundamentally eliminating mechanical friction. However, existing magnetic levitation fans still face the following challenges:

[0004] (1) The rotor is prone to radial displacement and axial vibration when suspended, resulting in poor positioning stability;

[0005] (2) Ensuring that the rotor smoothly and reliably enters the preset suspension center position from a stationary state is a key challenge in implementation;

[0006] (3) Traditional multi-degree-of-freedom magnetic levitation systems often require multiple independent electromagnets and sensors, resulting in complex structure installation and high cost. Summary of the Invention

[0007] Therefore, it is necessary to provide a suspended shaftless cooling fan and its control method, the specific technical solution of which is as follows.

[0008] A suspended shaftless cooling fan includes:

[0009] The suspended blade includes a suspension cylinder and blades fixed inside the suspension cylinder;

[0010] A fan frame, wherein an annular groove is provided inside the fan frame to adapt to the outer wall of the suspension cylinder, and a magnetic levitation positioning magnet assembly and a magnetic levitation drive assembly are provided between the annular groove and the outer wall of the suspension cylinder;

[0011] The magnetic levitation drive assembly includes a rotor magnet ring disposed on the outer wall of the levitation cylinder and an electromagnetic drive coil winding adapted to the rotor magnet ring disposed in the annular groove.

[0012] The magnetic levitation positioning magnet assembly includes a first positioning magnet and a second positioning magnet respectively provided at both ends of the outer wall of the levitation cylinder, and a first positioning winding and a second positioning winding respectively provided at the two ends of the annular groove; the first positioning winding and the second positioning winding are evenly arranged around the center of the annular groove.

[0013] The electromagnetic drive coil winding and the electromagnetic drive coil winding are electrically connected to the controller.

[0014] Furthermore, the outer wall of the suspension cylinder is provided with tapered hole plates at both ends, and the first positioning magnet and the second positioning magnet are provided on the inner wall of the tapered hole plates; the groove walls at both ends of the annular groove are provided with a sloped surface structure, and the first positioning winding and the second positioning winding are provided on the sloped surface structure.

[0015] Furthermore, the slope inclination of the inverted slope structure and the cone inclination of the cone plate are 65°–75°.

[0016] Furthermore, both the first positioning winding and the second positioning winding include a first bracket and a positioning coil winding. The cross-section of the first bracket is I-shaped, and the coil of the positioning coil winding is wound around the support rod in the middle of the first bracket.

[0017] Furthermore, the rotor magnet ring is fixed on the outer wall of the suspension cylinder, and the electromagnetic drive coil winding includes a positioning ring disposed in the annular groove and a second bracket protruding from the inner wall of the positioning ring, the second bracket being provided with a drive coil.

[0018] Furthermore, the second bracket has a T-shaped cross-section, and the drive coil is wound around the support rod in the middle of the drive coil.

[0019] A control method for a suspended shaftless cooling fan, as described above, specifically includes: symmetrically arranging multiple first distance sensors and second distance sensors on the groove walls at both ends of an annular groove; the first distance sensors and second distance sensors respectively measuring the distances of the first positioning winding and the second positioning winding from the first positioning magnet and the second positioning magnet as J1. n J2 n ; each J2 n Subtract the corresponding J1 n The absolute value after that is the distance difference X n If the distance difference X nIf the error is less than or equal to 1mm, determine whether to input the operating current I3 into the electromagnetic drive coil winding to start the fan; if it is greater than 1mm, adjust the input current I1 of the first positioning winding and the second positioning winding. n I2 n The value.

[0020] Furthermore, the above-mentioned adjustment of input current I1 n I2 n The specific method is as follows:

[0021] S1. Obtain the magnetic induction intensity of the first positioning magnet as B1 and the magnetic induction intensity of the second positioning magnet as B2;

[0022] S2. Fifteen evenly arranged first and second positioning windings are set in the annular groove, with the current of each winding being I11, I12, I13...I1 15 and I21, I22, I23...I2 15 The distance between each first positioning winding and the first positioning magnet is J11, J12, J13, ... J1 15 The distance between each second positioning winding and the second positioning magnet is J21, J22, J23...J2 15 ;

[0023] S3. Calculation , , , ... Recognize X1, X2, X3, X4...X 15 The value of X1, X2, X3...X is used to determine the value of X. 15 If the thickness is ≤1mm, then input the working current I3 into the electromagnetic drive coil winding to start the fan. If this condition is not met, proceed to the next step of calculation.

[0024] S4. Compare J2 n With J1 n The size, assuming J1 n If it is smaller, increase I1. n Current, the required increase in current value After adjustment, return to step S3 until X1, X2, X3...X are satisfied. 15 ≤1mm.

[0025] Furthermore, during fan rotation, dynamic monitoring is performed, and an electromagnetic force model F between each positioning winding and its corresponding positioning magnet is established using the current value I and the gap J. ,in, φ Let F1 be a force constant and N be the number of coil turns. Then, the electromagnetic forces of each first positioning winding and second positioning winding are F1 and F2, respectively.n F2 n Establish a fan blade stress assessment model V. ,in, ε The coefficient of force on both sides of the fan blade. κ The maximum uneven stress coefficient of the fan blades is given; a comprehensive vibration parameter evaluation model G is established. Where τ is the impeller force coefficient, λ G is the speed coefficient, and R is the impeller radius; if G is not within the set range, G max Inside, another assumption If the current is at its maximum, then I21 will be adjusted, and the increase in current will be [value missing]. Until within range G max Inside.

[0026] Furthermore, the upper limit of the current I1 in the first positioning winding is set to I1. max When I1 is adjusted to I1 max G is still not satisfied. max When the value of G is within the specified range, it is considered that the dust accumulation on the fan is serious, the dust cleaning mode is activated, G is recorded as G0 at this time, and a reverse working current I3 is input to the electromagnetic drive coil winding to start the fan reversal to clean the dust.

[0027] The theoretical current value of the first positioning winding is set to I10. After the fan stops, the current of the second positioning winding returns to zero. At this time, the currents of each first positioning winding are recorded as I11, I12, I13...I1 15 The intervals at this time are J11, J12, J13, ... J1 15 Set J1 n The target value is J10. If the target value is not reached, the current I1 is adjusted. n The adjusted current is After adjustment, J1 was recalculated. n The value, until Establish evaluation model D. The rotation speed for reverse dust removal is... until satisfied ,in, ξ Represents the vibration coefficient. ψ Represents the dust coefficient. η This represents the reversal vibration value coefficient.

[0028] Compared with existing technologies, the present invention has the following advantages:

[0029] (1) The suspended shaftless cooling fan and its control method of the present invention adopt a completely contactless magnetic levitation support and electromagnetic drive scheme, which completely eliminates the traditional mechanical bearing, thereby completely eliminating the friction loss, efficiency reduction, heat generation and wear problems caused by mechanical contact, and greatly improving the service life, operating efficiency and reliability of the product.

[0030] (2) The suspended shaftless cooling fan and its control method of the present invention monitor the rotor position in real time through multiple sets of distance sensors, and automatically adjust the current before starting to make the rotor accurately centered (control distance difference ≤ 1mm), ensuring that the fan can always start from the best position, avoiding vibration, noise or even the risk of rubbing due to eccentric starting, and greatly improving the reliability and safety of starting.

[0031] (3) When the current adjustment reaches the upper limit and still cannot meet the vibration requirements, the controller can intelligently determine that the problem is not an electrical or control fault, but a physical imbalance caused by dust accumulation, and automatically trigger the reverse dust cleaning mode. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application 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 application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a three-dimensional structural view of the suspended shaftless cooling fan of the present invention;

[0034] Figure 2 The structural explosion of the suspended shaftless cooling fan of the present invention Figure 1 ;

[0035] Figure 3 The structural explosion of the suspended shaftless cooling fan of the present invention Figure 2 ;

[0036] Figure 4 The structural explosion of the suspended shaftless cooling fan of the present invention Figure 3 ;

[0037] Figure 5 This is an enlarged exploded view of the suspension cylinder structure in this invention;

[0038] Figure 6 This is a structural cross-sectional view of the suspended shaftless cooling fan of the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 101, Suspension cylinder; 1011, Conical perforated plate; 102, Blade; 201, Fan frame; 202, Annular groove; 2021, Inclined surface structure; 301, Magnetic levitation positioning magnet assembly; 302, Magnetic levitation drive assembly; 3021, Rotor magnet ring; 3022, Electromagnetic drive coil winding; 3023, Positioning ring; 3024, Second bracket; 3025, Drive coil; 3011, First positioning magnet; 3012, Second positioning magnet; 3013, First positioning winding; 3014, Second positioning winding; 3015, First bracket; 3016, Positioning coil winding. Detailed Implementation

[0041] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0042] The embodiments of the present invention will now be described.

[0043] Reference Figures 1-6 As shown, this embodiment provides a suspended shaftless cooling fan, including: suspended blades, the suspended blades including a suspension cylinder 101 and blades 102 fixedly disposed inside the suspension cylinder 101; a fan frame 201, the fan frame 201 having an annular groove 202 adapted to the outer wall of the suspension cylinder 101, a magnetic levitation positioning magnet assembly 301 and a magnetic levitation drive assembly 302 disposed between the annular groove 202 and the outer wall of the suspension cylinder 101; the magnetic levitation drive assembly 302 includes a rotor magnet ring 3021 disposed on the outer wall of the suspension cylinder 101 and a rotor magnet ring 3021 disposed in the annular groove 202. The rotor magnet ring 3021 is adapted to the electromagnetic drive coil winding 3022; the magnetic levitation positioning magnet assembly 301 includes a first positioning magnet 3011 and a second positioning magnet 3012 respectively provided at both ends of the outer wall of the suspension cylinder 101, and a first positioning winding 3013 and a second positioning winding 3014 respectively provided at the two ends of the groove wall of the annular groove 202; the first positioning winding 3013 and the second positioning winding 3014 are evenly arranged around the center of the annular groove 202; the electromagnetic drive coil winding 3022 and the electromagnetic drive coil winding 3022 are electrically connected to the controller.

[0044] The suspended shaftless cooling fan of the present invention consists of two main parts: a suspended blade and a fan frame 201. Two major functional components are integrated in the gap between the annular groove 202 and the suspended cylinder 101 within the fan frame 201: a magnetic levitation positioning magnet assembly 301 and a magnetic levitation drive assembly 302. The magnetic levitation drive assembly 302 consists of a rotor magnet ring 3021 mounted on the suspended cylinder 101 and an electromagnetic drive coil winding 3022 mounted in the annular groove 202. The magnetic levitation positioning magnet assembly 301 consists of a first positioning magnet 3011 and a second positioning magnet 3012 mounted at both ends of the suspended cylinder 101 at an angle, and a first positioning winding 3013 and a second positioning winding 3014 mounted at the corresponding ends of the annular groove 202 at an angle. The first positioning magnet 3011 and the second positioning magnet 3012 are hollow conical structures, and these windings are evenly distributed around the center. All electromagnetic coil windings are electrically connected to a controller.

[0045] The levitation principle is as follows: After being energized, the first positioning winding 3013 and the second positioning winding 3014 generate a controlled electromagnetic field, which interacts with the corresponding first positioning magnet 3011 and second positioning magnet 3012 to produce an electromagnetic force that includes both axial and radial components. These two sets of forces work together to stably constrain the levitation blade to the central position of the annular groove 202, achieving contactless magnetic levitation.

[0046] The driving principle is as follows: the controller supplies multiphase alternating current to each electromagnetic drive coil winding 3022, generating a rotating magnetic field. This magnetic field interacts with the rotor magnet ring 3021 fixed on the suspension cylinder 101, generating a Lorentz force, thereby driving the entire suspension blade to rotate frictionlessly around its central axis.

[0047] In actual use: After the user connects the power, the controller first activates the positioning system, and current is supplied to each of the first positioning windings 3013 and the second positioning windings 3014, attracting and stably suspending the suspension cylinder 101 at the center of the fan frame 201. Subsequently, the controller outputs drive current to each electromagnetic drive coil winding 3022, and the fan begins to rotate and deliver air. During operation, the controller continuously monitors and fine-tunes the current of each winding to maintain stable suspension and uniform rotation.

[0048] This cooling fan fundamentally eliminates mechanical friction and wear, significantly reducing operating noise and improving efficiency and lifespan. The tilted positioning magnets and windings enable combined radial and axial control, resulting in a compact structure and highly efficient control.

[0049] Inclined first and second positioning magnets are respectively installed at both ends of the outer wall of the suspension cylinder. Multiple sets of first and second positioning windings are also arranged at an angle on the corresponding end walls of the annular groove. When energized, these windings generate electromagnetic force, which interacts with the inclined positioning magnets. This ingenious inclined design decomposes the electromagnetic force into axial and radial components, suspending the blade in the air and constraining it to a central position, preventing collisions with the groove walls. By independently controlling the current in each set of windings at both ends, the blade's attitude in space can be precisely adjusted.

[0050] Moreover, the first positioning winding 3013, the second positioning winding 3014, and the electromagnetic drive coil winding 3022 can be installed in the cylindrical fan frame 201, and can be modularly installed with the suspended blades. The structure is simple, easy to manufacture and assemble, and has low production cost.

[0051] Specifically, the outer wall of the suspension cylinder 101 is provided with conical plate 1011 at both ends, and the first positioning magnet 3011 and the second positioning magnet 3012 are provided on the inner wall of the conical plate 1011; the groove walls at both ends of the annular groove 202 are provided with a sloped surface structure 2021, which is parallel to the conical surface of the conical plate 1011, the first positioning magnet 3011 and the second positioning magnet 3012, and the first positioning winding 3013 and the second positioning winding 3014 are provided on the sloped surface structure 2021; the slope of the sloped surface structure 2021 and the slope of the conical surface of the conical plate 1011 are 65°-75°. In this embodiment, the first positioning magnet 3011 and the second positioning magnet 3012 are mounted at both ends of the suspension cylinder 101 via tapered perforated plates 1011. The annular groove 202 has inverted slope structures 2021 at both ends to mount the first positioning winding 3013 and the second positioning winding 3014. The tapered perforated plates 1011 and the inverted slope structures 2021 provide precise mounting references for the magnets and windings. The first positioning winding 3013 and the second positioning winding 3014 are hollow tapered shell structures. The first positioning magnet 3011 and the second positioning magnet 3012 are fitted against the tapered surface of the tapered perforated plates 1011, ensuring that the direction of the magnetic field force is controllable and efficient. The optimized mechanical structure ensures uniform air gap in the magnetic circuit, improving suspension efficiency and control accuracy. The defined inclination range is optimized to ensure sufficient suspension support force and axial constraint force on the suspension blades, while maintaining a compact structure.

[0052] Furthermore, both the first positioning winding 3013 and the second positioning winding 3014 include a first support 3015 and a positioning coil winding 3016. The first support 3015 has an I-shaped cross-section, and the coil of the positioning coil winding 3016 is wound around a support rod in the middle of the first support 3015. In this embodiment, each first positioning winding 3013 and second positioning winding 3014 consists of an I-shaped first support 3015 and a positioning coil winding wound around its middle support rod. The I-shaped support acts as a skeleton and a heat sink. The middle support rod provides the base for coil winding, and the flanges at both ends are used for fixed installation on the sloped surface structure and increase the heat dissipation area. The coil is tightly wound on the support rod to form concentrated magnetic poles. The coil is wound on the I-shaped support to form an independent winding unit, which is then mass-produced and installed on the slope of the fan frame. Modularizing the windings provides excellent mechanical support, heat dissipation paths, and magnetic field concentration, simplifying production and assembly processes and improving the structural strength, heat dissipation performance, and reliability of the windings. The I-shaped design makes the magnetic field more concentrated, resulting in higher efficiency, while also facilitating standardized production and maintenance.

[0053] Specifically, the rotor magnet ring 3021 is fixed to the outer wall of the suspension cylinder 101. The electromagnetic drive coil winding 3022 includes a positioning ring 3023 disposed in the annular groove 202 and a second bracket 3024 protruding from the inner wall of the positioning ring 3023. The second bracket 3024 is provided with a drive coil 3025. In this embodiment, the positioning ring 3023 is the basic mounting platform for the electromagnetic drive coil winding 3022, ensuring the concentricity of all drive coil units. The second bracket 3024 supports the drive coil 3025 and extends it to a predetermined position near the rotor magnet ring 3021 for effective electromagnetic coupling. Multiple second brackets 3024 with drive coils 3025 are uniformly mounted circumferentially on the positioning ring 3023, forming a multi-pole drive winding array. This provides a modular, high-precision drive winding installation scheme, ensuring a uniform and symmetrical drive magnetic field and reducing torque fluctuations. It guarantees the high efficiency and stability of the drive assembly, reduces vibration and noise, and the modular design facilitates manufacturing and maintenance.

[0054] Specifically, the second bracket 3024 has a T-shaped cross-section, and the drive coil 3025 is wound around the support rod in the middle of the drive coil 3025. The T-shaped bracket can firmly fix the coil and provide sufficient space for winding and heat dissipation.

[0055] This suspended shaftless cooling fan has the advantages of no mechanical friction and an ultra-long lifespan; moreover, without a central hub or traditional shaft, the airflow area has increased from about 75% to about 95%; it operates stably and can self-adjust according to the environment; and due to the fan's self-balancing function, it has low noise.

[0056] A control method for a suspended shaftless cooling fan includes: symmetrically arranging multiple first distance sensors and second distance sensors on the groove walls at both ends of an annular groove 202; the multiple first distance sensors and second distance sensors are mounted on the inverted slope structure 2021 on the groove walls at both ends of the annular groove 202; the multiple first distance sensors are correspondingly positioned next to each first positioning winding 3013; and the multiple second distance sensors are correspondingly positioned next to each second positioning winding 3014; the detection heads of the first distance sensors and second distance sensors are aligned with the conical surfaces of the first positioning magnet 3011 and the second positioning magnet 3012; and the first distance sensors and second distance sensors respectively measure the distance J1 between the first positioning winding 3013 and the second positioning winding 3014 and the first positioning magnet 3011 and the second positioning magnet 3012. n J2 n ; each J2 n Subtract the corresponding J1 n The absolute value after that is the distance difference X n If the distance difference X n If the error is less than or equal to 1 mm, determine that the operating current I3 is input to the electromagnetic drive coil winding 3022 to start the fan; if it is greater than 1 mm, adjust the input current I1 of the first positioning winding 3013 and the second positioning winding 3014. n I2 n The value. Adjust the input current I1. n I2 n The specific method is as follows:

[0057] S1. Obtain the magnetic induction intensity of the first positioning magnet 3011 as B1 and the magnetic induction intensity of the second positioning magnet 3012 as B2;

[0058] S2. Fifteen evenly arranged first positioning windings 3013 and second positioning windings 3014 are provided in the annular groove 202, and the current of each winding is I11, I12, I13...I1 15 and I21, I22, I23...I2 15 The distance between each first positioning winding 3013 and the first positioning magnet 3011 is J11, J12, J13, ... J1 15 The distance between each second positioning winding 3014 and the second positioning magnet 3012 is J21, J22, J23...J2 15 ;

[0059] S3. Calculation , , , ... Recognize X1, X2, X3, X4...X 15 The value of X1, X2, X3...X is used to determine the value of X. 15 If the thickness is ≤1mm, then input the working current I3 into the electromagnetic drive coil winding 3022 to start the fan. If this condition is not met, proceed to the next step of the calculation.

[0060] S4. Compare J2 n With J1 n The size, assuming J1 n If it is smaller, increase I1. n Current, the required increase in current value After adjustment, return to step S3 until X1, X2, X3...X are satisfied. 15 ≤1mm.

[0061] Distance sensors are installed at both ends of the annular groove 202 to measure the gap (J1) between each positioning winding and the corresponding positioning magnet in real time. n or J2 n Calculate the gap difference X at corresponding positions at both ends. n Ideally (with blades suspended horizontally), all X n It should be close to 0. Set a threshold (e.g., 1mm), and allow the fan to start only when all Xn values ​​are less than this threshold. If any Xn is too large, it indicates that the blades are tilted at that position. The control system adjusts the current (I1) in the positioning winding near that position. n or I2 n This is achieved by changing the magnitude of the electromagnetic force, thereby pushing the blades back to their equilibrium position. The required increase in current is calculated to quickly achieve balance. This ensures that the fan is in a near-perfect balanced state before startup, avoiding startup failure, severe vibration, or noise caused by initial imbalance.

[0062] Specifically, when the fan rotates, the fan is dynamically monitored, and an electromagnetic force model F between each positioning winding and the corresponding positioning magnet is established using the current value I and the gap J. ,in, φ Let F1 be a force constant and N be the number of coil turns. Then, the electromagnetic forces of the first positioning winding 3013 and the second positioning winding 3014 are respectively F1 n F2 nThe main purpose of establishing this model is to determine the force on each winding in its current state. The force received by the winding is equivalent to the force on the frame at this point. The fan vibration value is reflected in the uneven change of the force value, which is used for the next step of evaluating the fan vibration.

[0063] Then, a fan blade stress evaluation model V is established. ,in, ε The coefficient of force on both sides of the fan blade. κ This is the maximum uneven force coefficient of the fan blades. This model is mainly used to evaluate the current uneven force state of the fan.

[0064] Next, a comprehensive vibration parameter evaluation model G is established.

[0065] Where τ is the impeller force coefficient, λ G is the speed coefficient, and R is the impeller radius; if G is not within the set range, G max Inside, another assumption If the current is at its maximum, then I21 will be adjusted, and the increase in current will be [value missing]. Until within range G max The internal measurement is used to assess the magnitude of the positioning current required to adjust the vibration value during operation.

[0066] In this embodiment, after the fan rotates, the control system continues to operate, and a more accurate electromagnetic force model (F1) is established through real-time current I and gap J. n Or F2 n Then, by integrating all forces, a fan blade force assessment model V and a comprehensive vibration parameter assessment model G are constructed. The G value is a quantitative assessment of the overall vibration level of the fan. The G value is compared in real time with a preset safety range Gmax. If the G value exceeds the range, it indicates that the fan has experienced dynamic imbalance due to dust accumulation or other reasons. The system will identify the point of maximum force and fine-tune the current of the winding corresponding to that point to counteract the unbalanced force, bringing the G value back to the normal range. This achieves active vibration reduction of the fan during operation, maintaining smooth and quiet operation at high speeds, and improving the high-end performance and user experience of the product.

[0067] In this embodiment, the upper limit value of the current I1 of the first positioning winding 3013 is set to I1. max When I1 is adjusted to I1 max G is still not satisfied. max When the value of G is within the specified range, it is considered that the dust accumulation on the fan is serious, the dust cleaning mode is activated, G is recorded as G0 at this time, and a reverse working current I3 is input to the electromagnetic drive coil winding 3022 to start the fan reversal to clean the dust.

[0068] The theoretical current value of the first positioning winding 3013 is set to I10. After the fan stops, the current of the second positioning winding 3014 returns to zero. At this time, the currents of each of the first positioning windings 3013 are denoted as I11, I12, I13...I1 15 The intervals at this time are J11, J12, J13, ... J1 15 Set J1 n The target value is J10. If the target value is not reached, the current I1 is adjusted. n The adjusted current is After adjustment, J1 was recalculated. n The value, until Establish evaluation model D. The rotation speed for reverse dust removal is... until satisfied ,in, ξ Represents the vibration coefficient. ψ Represents the dust coefficient. η This represents the vibration coefficient during reversal. When the controller system can no longer control the vibration (G value) within the allowable range through current adjustment (i.e., the current has reached the upper limit I1max), the system determines that this is caused by severe dust accumulation. At this time, the system automatically records the current vibration level G0 and controls the fan to reverse for dust removal. During reversal, the airflow direction changes, which can blow off the dust attached to the blades. The system also establishes an evaluation model D, which quantifies the amount of dust based on the additional current consumed to maintain balance, and intelligently determines the speed and time of reversal dust removal until the vibration level drops to the expected value. This achieves a completely self-maintenance function without manual intervention. It greatly improves the long-term operational reliability and lifespan of the fan in harsh or dusty environments, making it a truly "maintenance-free" intelligent fan.

[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above embodiments only illustrate one or more implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A control method for a suspended shaftless cooling fan, comprising: The suspension blade includes a suspension cylinder (101) and a blade (102) fixed inside the suspension cylinder (101). A fan frame (201) is provided with an annular groove (202) that is adapted to the outer wall of the suspension cylinder (101). A magnetic levitation positioning magnet assembly (301) and a magnetic levitation drive assembly (302) are provided between the annular groove (202) and the outer wall of the suspension cylinder (101). The magnetic levitation drive assembly (302) includes a rotor magnet ring (3021) provided on the outer wall of the levitation cylinder (101) and an electromagnetic drive coil winding (3022) provided in the annular groove (202) that is adapted to the rotor magnet ring (3021). The magnetic levitation positioning magnet assembly (301) includes a first positioning magnet (3011) and a second positioning magnet (3012) respectively provided at both ends of the outer wall of the levitation cylinder (101) and a first positioning winding (3013) and a second positioning winding (3014) respectively provided at both ends of the groove wall of the annular groove (202); the first positioning winding (3013) and the second positioning winding (3014) are evenly arranged around the center of the annular groove (202); The electromagnetic drive coil winding (3022) and the electromagnetic drive coil winding (3022) are electrically connected to the controller. The specific method includes: symmetrically arranging multiple first distance sensors and second distance sensors on the groove walls at both ends of the annular groove (202), wherein the first distance sensors and second distance sensors respectively measure the distance J1 between the first positioning winding (3013) and the second positioning winding (3014) and the first positioning magnet (3011) and the second positioning magnet (3012). n J2 n ; each J2 n Subtract the corresponding J1 n The absolute value after that is the distance difference X n If the distance difference X n If the error is less than or equal to 1 mm, determine that the working current I3 is input to the electromagnetic drive coil winding (3022) to start the fan; if it is greater than 1 mm, adjust the input current I1 of the first positioning winding (3013) and the second positioning winding (3014). n I2 n The value; Input current I1 n I2 n The specific adjustment method is as follows: S1. Obtain the magnetic induction intensity of the first positioning magnet (3011) as B1 and the magnetic induction intensity of the second positioning magnet (3012) as B2; S2. Fifteen evenly arranged first positioning windings (3013) and second positioning windings (3014) are set in the annular groove (202), and the current of each winding is I11, I12, I13...I1 15 and I21, I22, I23...I2 15 The distance between each first positioning winding (3013) and the first positioning magnet (3011) is J11, J12, J13, ... J1 15 The distance between each second positioning winding (3014) and the second positioning magnet (3012) is J21, J22, J23...J2 15 ; S3. Calculation , , , ... Recognize X1, X2, X3, X4...X 15 The value of X1, X2, X3...X is used to determine the value of X. 15 If the diameter is ≤1mm, then input the working current I3 into the electromagnetic drive coil winding (3022) to start the fan. If this condition is not met, proceed to the next step of calculation. S4. Compare J2 n With J1 n The size, assuming J1 n If it is smaller, increase I1. n Current, the required increase in current value After adjustment, return to step S3 until X1, X2, X3...X are satisfied. 15 ≤1mm.

2. The control method for a suspended shaftless cooling fan according to claim 1, characterized in that, The outer wall of the suspension cylinder (101) is provided with tapered hole plates (1011) at both ends, and the first positioning magnet (3011) and the second positioning magnet (3012) are provided on the inner wall of the tapered hole plate (1011); the groove walls at both ends of the annular groove (202) are provided with inverted slope structure (2021), and the first positioning winding (3013) and the second positioning winding (3014) are provided on the inverted slope structure (2021).

3. The control method for a suspended shaftless cooling fan according to claim 2, characterized in that, The slope inclination of the slope structure (2021) and the cone inclination of the cone plate (1011) are 65°–75°.

4. The control method for a suspended shaftless cooling fan according to claim 2, characterized in that, Both the first positioning winding (3013) and the second positioning winding (3014) include a first bracket (3015) and a positioning coil winding (3016). The first bracket (3015) has an I-shaped cross-section, and the coil of the positioning coil winding (3016) is wound around the support rod in the middle of the first bracket (3015).

5. The control method for a suspended shaftless cooling fan according to claim 4, characterized in that, The rotor magnet ring (3021) is fixed on the outer wall of the suspension cylinder (101). The electromagnetic drive coil winding (3022) includes a positioning ring (3023) disposed in the annular groove (202) and a second bracket (3024) protruding from the inner wall of the positioning ring (3023). The second bracket (3024) is provided with a drive coil (3025).

6. The control method for a suspended shaftless cooling fan according to claim 5, characterized in that, The second bracket (3024) has a T-shaped cross-section, and the drive coil (3025) is wound around the support rod in the middle of the drive coil (3025).

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