Efficient magnetic suspension magnetic force pump bearing structure and control method thereof

Abstract

The application relates to a high-efficiency magnetic suspension magnetic force pump bearing structure and a control method thereof, which comprises a pump shell, a main shaft, an internal thread bearing seat and a tapered roller bearing, one end of the main shaft is provided with a flat key groove, the other end is supported through the tapered roller bearing, the pump shell is provided with an internal thread flange port, the outer side of the internal thread bearing seat is provided with a screwing transmission part, and the outer wall of the pump shell is provided with a sensing module; the air gap is finely adjusted to a critical balance interval through the internal thread bearing seat, a magnetic force driver is started to make the main shaft suspended and rotate, the clearance fit between the flat key groove and the flat key limits the radial swing, the sensing module monitors the vibration in real time, the electromagnetic force is dynamically adjusted by a PLC controller to maintain the suspension stability; when power is cut off or the magnetic force is invalid, the main shaft is mechanically supported by the tapered roller bearing, the bore sweeping accident is avoided, the magnetic suspension high-efficiency no-wear operation and the mechanical redundant safety guarantee are considered, the air gap is accurately adjustable, the radial vortex is inhibited, the overload stop protection is provided, and the maintenance and dismounting are convenient.

Description

Technical Field

[0001] This invention relates to the field of magnetic levitation pumps and related technologies, and particularly to a high-efficiency magnetic levitation pump bearing structure and its control method. Background Technology

[0002] Magnetic pumps, as leak-free fluid transport devices, occupy an important position in modern industry. Traditional magnetic pumps mainly rely on an inner magnetic rotor, an isolation sleeve, and an outer magnetic rotor for torque transmission, supported by sliding bearings such as silicon carbide bearings. However, with the increasing demands for equipment efficiency and lifespan, magnetic levitation pumps have emerged. They utilize magnetic force to suspend the pump shaft in the air, completely eliminating mechanical friction between bearings, thereby achieving extremely high operating efficiency and extremely low wear.

[0003] Despite the significant advantages mentioned above, magnetic levitation pumps still suffer from the following key drawbacks and pain points in practical engineering applications and existing technologies:

[0004] 1. Lack of effective mechanical safety redundancy: Existing magnetic levitation pumps typically rely heavily on external controllers and electromagnetic coils to maintain levitation. However, in the event of a sudden power outage, controller failure, or strong electromagnetic interference, the high-speed rotating main shaft will instantly lose levitation force. If there is no reliable mechanical support structure, the main shaft will directly "slam" onto the pump casing or stator, resulting in an extremely serious "rotor rubbing" accident, where the rotor rubs against the stator at high speed, causing instantaneous overheating and burning or jamming. Existing technology lacks purely mechanical protective bearings that can seamlessly and smoothly switch to magnetic levitation.

[0005] 2. The magnetic air gap is difficult to adjust precisely. The levitation force applied to the spindle by the magnetic actuator is directly related to the working distance of the "air gap" between the spindle and the inner magnetic ring. Even a difference of a few tenths of a millimeter in distance will cause a drastic change in the magnetic attraction force. In traditional designs, the rotor position is fixed after assembly and cannot be fine-tuned later. If the machining tolerance causes the air gap to be too large, the magnetic force will be insufficient and the spindle will not be able to levitate at all. If the air gap is too small, it is easy to be stuck. How to design a simple and reliable mechanical structure to adjust this air gap is a blind spot in the existing technology.

[0006] 3. Radial eddy currents exist during high-speed operation. Due to fluid disturbance and the imperfect symmetry of the magnetic field, the suspended main shaft is prone to "radial eddy currents" when rotating at high speed, that is, it swings around the central axis. To suppress this swaying, existing technologies often require extremely complex active magnetic levitation control algorithms and expensive displacement sensors, resulting in high equipment costs. In extreme cases, if the complex electronic control algorithm does not react in time, it will cause the shaft to shake violently or even hit the wall.

[0007] 4. Maintenance and disassembly are extremely complicated. The magnetic force inside the magnetic levitation pump is very strong. When it is necessary to disassemble the main shaft to replace the seal or bearing, maintenance personnel often have to overcome the huge magnetic force and use a special puller to forcibly pull the shaft out. This process is not only laborious, but also very easy to damage the magnetic components or isolation sleeve.

[0008] In summary, there is an urgent need for a high-efficiency magnetic levitation magnetic pump bearing structure and its control method to solve the above problems. Summary of the Invention

[0009] The purpose of this invention is to address the shortcomings of existing technologies by incorporating an internally threaded bearing housing that mates with the pump housing's threads, enabling convenient fine-tuning of the air gap between the main shaft and the external magnetic actuator, thereby ensuring the precise establishment of the initial magnetic levitation state. Simultaneously, a tapered roller bearing is configured as a purely mechanical redundancy protection, capable of instantly catching the falling main shaft in the event of a sudden power outage or magnetic failure, effectively preventing rotor rubbing accidents. Furthermore, the mating of the keyway on the main shaft with the key inside the pump housing limits radial oscillation during high-speed rotation, and a sensing module monitors vibration or pressure signals in real time, dynamically adjusting the electromagnetic force in conjunction with a PLC controller to suppress radial eddying and maintain levitation stability. During maintenance, simply rotating the internally threaded bearing housing in the reverse direction allows the main shaft to easily disengage from the strong magnetic constraint, significantly simplifying the disassembly process. The synergistic effect of these structures systematically solves the technical challenges of existing magnetic levitation pumps in terms of safety redundancy, air gap adjustment, dynamic stability, and ease of maintenance.

[0010] To achieve the above objectives, the present invention provides the following technical solution:

[0011] A high-efficiency magnetic levitation magnetic pump bearing structure includes a pump housing, a main shaft, an internal thread bearing housing, and a tapered roller bearing. The main shaft is connected through the pump housing, and one end of the main shaft is provided with a flat keyway. The other end of the main shaft is supported by the tapered roller bearing. One end of the pump housing is provided with an internal thread flange port. The inner side of the internal thread bearing housing is used to form a clearance fit with the main shaft, and the outer side of the internal thread bearing housing is provided with a screw-in transmission part. A sensing module is provided on the outer wall of the pump housing.

[0012] As a preferred embodiment, the tapered roller bearing is a double-row tapered roller bearing, with the outer ring of the tapered roller bearing fixed to the rear end of the pump housing and the inner ring fitted and locked to the main shaft.

[0013] As a preferred embodiment, the keyway is a semi-open keyway, and the length of the keyway extends to one end of the main shaft near the internal thread bearing seat; the pump housing is provided with a keyway locking strip that is clearance-fitted with the keyway.

[0014] As a preferred embodiment, the sensing module is a pressure sensing module or an acceleration vibration sensing module, and the sensing module is embedded in a rectangular protrusion space on the outer wall of the pump housing. The sensing module is connected to a signal line, which is electrically connected to an external PLC controller, and the PLC controller is electrically connected to a magnetic actuator.

[0015] As a preferred embodiment, the outer periphery of the internal thread bearing housing is provided with flange mounting holes evenly distributed along the circumference, and locking bolts are provided in the flange mounting holes. The locking bolts are fixedly connected to the pump housing through the flange mounting holes.

[0016] A method for controlling the bearing structure of a high-efficiency magnetic levitation pump is characterized by the following step S1: rotating the internal thread bearing seat and fine-tuning its depth of screwing into the pump housing to adjust the air gap between the main shaft and the external magnetic actuator, so that the main shaft reaches the initial levitation state under the action of magnetic force.

[0017] Step S2: Start the external magnetic drive to drive the main shaft to rotate at high speed. During the rotation, the radial swing of the main shaft is limited by the cooperation between the flat keyway of the main shaft and the flat key in the pump housing.

[0018] Step S3: The sensing module acquires the vibration or pressure status signal of the spindle in real time and feeds the signal back to the PLC controller. The PLC controller adjusts the magnitude and phase of the electromagnetic force of the magnetic actuator according to the feedback signal to maintain the magnetic levitation balance.

[0019] Step S4: When a power outage or magnetic drive failure occurs, the main shaft loses its levitation force, falls instantly, and is supported purely mechanically by the tapered roller bearing to prevent the main shaft from making hard contact with the pump housing and rubbing against the rotor.

[0020] As a preferred embodiment, in step S1, by rotating the internal thread bearing seat, the air gap between the spindle and the external magnetic actuator is adjusted to between 0.5mm and 2.5mm, so that the spindle is in the critical balance range between magnetic attraction and mechanical support.

[0021] As a preferred embodiment, in step S3, when the sensing module detects that the radial vibration amplitude exceeds the set threshold, the PLC controller adjusts the phase of the main magnetic field of the magnetic drive and changes the tangential torque of the electromagnetic field to counteract the radial eddy current of the spindle.

[0022] As a preferred embodiment, the method further includes an overload protection step S5: when the sensing module detects that the internal pressure of the pump body exceeds the design pressure limit, the PLC controller actively cuts off the power supply of the magnetic drive, and the main shaft is rapidly displaced backward by the fluid counter-thrust, and the end face of the tapered roller bearing directly bears the ultimate axial load, forming a hard anti-reverse protection.

[0023] As another preferred option, the control method further includes equipment maintenance step S6: when it is necessary to disassemble the main shaft to replace the bearing, rotate the internal thread bearing seat in the opposite direction to make the main shaft move out of the pump housing. During the withdrawal process, the distance between the main shaft and the external magnetic drive increases, and the magnetic attraction weakens sharply until it breaks away from the magnetic restraint, thereby easily removing the entire rotor assembly.

[0024] The beneficial effects of this invention are:

[0025] (1) In this invention, by connecting the internal thread bearing seat to the pump housing by thread, the air gap between the main shaft and the external magnetic drive can be easily and accurately adjusted. The screw depth can be changed by simply rotating the bearing seat, thereby adjusting the air gap to the optimal working range and ensuring that the main shaft accurately reaches the initial suspension state under magnetic drive. This completely solves the industry blind spot problem of traditional magnetic levitation pumps being unable to levitate due to excessively large air gaps or being sucked up due to excessively small air gaps caused by machining tolerances, and greatly reduces the difficulty of assembly and debugging.

[0026] (2) This invention, based on magnetic levitation operation, is equipped with tapered roller bearings as pure mechanical redundancy protection. When a sudden power outage, controller failure, or strong electromagnetic interference causes the loss of levitation force, the main shaft drops instantly and is supported by the bearing, effectively avoiding a hard rubbing accident between the main shaft and the pump casing. At the same time, when the internal pressure of the pump exceeds the limit, the PLC controller actively cuts off the power supply, the main shaft moves backward under the fluid back thrust and the bearing end face bears the ultimate axial load, forming a hard back-stop protection, thus providing double safety protection for the magnetic levitation system and significantly improving the reliability and safety of equipment operation.

[0027] (3) The present invention utilizes the cooperation between the flat keyway on the main shaft and the flat key inside the pump housing to effectively limit the radial oscillation of the main shaft during high-speed rotation. At the same time, the vibration and pressure signals are monitored in real time by the sensing module, and the electromagnetic force of the magnetic drive is dynamically adjusted by the PLC controller to actively suppress radial eddy, thereby greatly improving the suspension stability. In addition, during maintenance and disassembly, only the internal thread bearing seat needs to be rotated in the opposite direction, and the main shaft can be moved outward and separated from the strong magnetic constraint of the magnetic drive. The rotor assembly can be easily removed without the need for a special puller tool, which simplifies the maintenance process and reduces maintenance costs and operational risks.

[0028] In summary, this equipment has the advantages of low assembly difficulty, easy debugging, high reliability, high safety factor, low maintenance cost, and low operational risk, and is especially suitable for the field of magnetic levitation magnetic pump technology. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0031] Figure 2 This is a schematic diagram of the sensing module in this invention.

[0032] Figure 3 This is a schematic diagram of the tapered roller bearing in this invention. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0034] Example 1

[0035] like Figures 1 to 3 As shown, the present invention provides a high-efficiency magnetic levitation magnetic pump bearing structure, including a pump housing 1, a main shaft 2, an internal thread bearing seat 3, and a tapered roller bearing 4. The main shaft 2 is connected through the pump housing 1, and one end of the main shaft 2 is provided with a flat keyway 21. The other end of the main shaft 2 is supported by the tapered roller bearing 4. One end of the pump housing 1 is provided with an internal thread flange port 11. The inner side of the internal thread bearing seat 3 is used to form a clearance fit with the main shaft 1, and the outer side of the internal thread bearing seat 3 is provided with a screw-in transmission part 5. The outer wall of the pump housing 1 is provided with a sensing module 12.

[0036] Furthermore, the tapered roller bearing 4 is a double-row tapered roller bearing, with its outer ring fixed to the rear end of the pump housing 1 and its inner ring fitted and locked to the main shaft 2. The outer ring's fixed position on the rear end of the pump housing 1 provides a rigid positioning base for the bearing, while the inner ring is tightly fitted and locked to the main shaft 2, ensuring synchronous high-speed rotation between the inner ring and the main shaft 2. When the magnetic levitation system is working normally, the bearing 4 is in a non-contact standby state and does not participate in load bearing. In the event of a power outage or magnetic drive failure, the main shaft 2 instantly loses its levitation force and falls. At this time, the inner ring falls with the main shaft 2, and the rollers roll in the double-row tapered raceway, converting the radial impact and axial movement of the main shaft 2 into rolling friction. The outer ring then transmits the load to the entire machine housing through the rear end of the pump housing 1, thereby... To avoid hard rubbing between the main shaft 2 and the pump housing 1; the double-row structure allows it to withstand axial forces in both directions and large radial loads simultaneously. In the overload protection step S5, when the main shaft 2 is displaced backward by the fluid back thrust, the end face of the bearing 4 can directly withstand the ultimate axial load, forming a hard stop, which further enhances the axial limiting capability; the design of locking the inner ring to the main shaft 2 ensures that there is no relative sliding between the inner ring of the bearing 4 and the main shaft 2 when rotating in magnetic levitation, avoiding additional wear. At the same time, the outer ring fixed to the rear end of the pump housing 1 provides stable support rigidity and alignment accuracy, so that the bearing 4 can instantly establish a reliable mechanical support path when receiving emergency loads. Moreover, its rolling contact mode has lower frictional heat and higher instantaneous impact resistance compared to sliding bearings.

[0037] In summary, the double-row tapered roller bearing 4, with its outer ring fixed to the rear end of the pump housing 1 and its inner ring locked to the main shaft 2, not only does not interfere with the magnetic levitation operation under normal conditions, but also smoothly supports the main shaft 2 in the event of failure through pure mechanical rolling. It has multiple advantages such as bidirectional axial load-bearing, radial limiting, overload prevention, and low wear, providing efficient, reliable, and seamless switching safety redundancy protection for the magnetic levitation system.

[0038] Furthermore, the keyway 21 is a semi-open keyway, and the length of the keyway 21 extends to one end of the main shaft 2 near the internal thread bearing seat 3; the pump housing 1 is provided with a keyway locking strip 22 that is clearance-fitted with the keyway 21. When the main shaft 2 is suspended and rotated at high speed, the keyway locking strip 22 is embedded in the keyway 21. The clearance fit between the two is neither too large nor too small, thus achieving radial limiting. That is, the side wall of the keyway 21 and the side of the keyway locking strip 22 form a constraint in the circumferential direction, thereby effectively limiting the radial sway and vortex of the main shaft 2 caused by fluid disturbance or magnetic field asymmetry. At the same time, due to the existence of the clearance fit, the main shaft 2 is allowed to move freely when there is a small axial movement or thermal expansion, avoiding jamming.

[0039] In addition, the semi-open structure allows the keyway 21 to open at the end of the spindle 2, which facilitates the smooth insertion of the keyway locking strip 22 during assembly. At the same time, during maintenance and disassembly, the internal thread bearing seat 3 is rotated in the opposite direction to allow the spindle 2 to exit outward. The keyway 21 can slide off along the keyway locking strip 22 without hindering the axial disassembly of the spindle 2.

[0040] By using a purely mechanical keyway fit, radial instability under high-speed rotation can be suppressed without complex sensing and active control, significantly improving the stability of magnetic levitation operation. At the same time, the semi-open extension structure takes into account the convenience of axial adjustment and disassembly, and the clearance fit avoids over-positioning and frictional heat generation. The structure is simple, reliable, and low-cost. Working in conjunction with the magnetic levitation system, it further enhances the dynamic stability and maintenance friendliness of the overall bearing structure.

[0041] Furthermore, the sensing module 12 is a pressure sensing module or an acceleration vibration sensing module, and the sensing module 12 is embedded in the rectangular protrusion space on the outer wall of the pump housing 1. The sensing module 12 is connected to a signal line, which is electrically connected to an external PLC controller. The PLC controller is electrically connected to a magnetic drive. The sensing module 12 is a pressure sensing module or an acceleration vibration sensing module, and is embedded in the rectangular protrusion space on the outer wall of the pump housing 1. This rectangular protrusion space provides an independent installation position for the sensing module 12, making it closer to the outer wall of the pump housing 1 to sense the housing vibration or internal fluid pressure changes caused by the operation of the main shaft 2, while avoiding interference with rotating parts.

[0042] The sensing module 12 transmits the collected vibration or pressure signals to the external PLC controller in the form of electrical signals via signal lines. The PLC controller, as the core of data processing and decision-making, has built-in preset thresholds and control algorithms to analyze and judge the received signals in real time. When the radial vibration amplitude exceeds the set threshold or the pressure is abnormal, the PLC controller outputs an adjustment command and drives the magnetic actuator through an electrical connection to change the magnitude and phase of its electromagnetic force, thereby actively adjusting the magnetic field distribution to suppress radial eddy current or maintain magnetic levitation balance.

[0043] The sensing module 12 can flexibly select pressure or acceleration type to adapt to different working conditions. It is embedded in the rectangular protrusion space, which not only ensures the accuracy of signal acquisition but also enhances the anti-interference capability. The signal line connection method ensures reliable transmission. The PLC controller has high-speed response and precise control capabilities, and can dynamically correct magnetic parameters in a closed loop. It effectively avoids complex displacement sensors and high-cost control algorithms. The electrical connection to the magnetic actuator realizes fast closed-loop control from signal perception to execution intervention, which significantly improves the adaptive stability and fault response efficiency of the magnetic levitation system.

[0044] Furthermore, the outer periphery of the internally threaded bearing housing 3 is provided with flange mounting holes 31 evenly distributed along the circumference. Locking bolts are installed within the flange mounting holes 31, and these locking bolts are used to fix the pump housing 1 through the flange mounting holes 31. The internally threaded bearing housing 3 is first rotated to screw its threads into the internally threaded flange end of the pump housing 1. 11. After the air gap between the main shaft 2 and the external magnetic drive is precisely adjusted, after adjusting to the required position, align the flange mounting holes 31 with the corresponding threaded holes on the pump housing 1, and screw in the locking bolts in sequence. The bolt preload force makes the flange end face of the internal thread bearing seat 3 fit tightly with the end face of the pump housing 1, thereby achieving axial and circumferential dual positioning and locking of the internal thread bearing seat 3 on the pump housing 1, preventing the internal thread bearing seat 3 from loosening or rotating due to vibration or magnetic force during operation, and thus avoiding air gap parameter drift.

[0045] The flange mounting holes 31 are evenly distributed around the circumference, ensuring that the preload applied by the locking bolts is uniform and symmetrical, preventing uneven loading or tilting of the internal thread bearing housing 3, and ensuring the coaxiality of the main shaft 2 and the pump housing 1. At the same time, the multi-point locking method has higher vibration resistance and anti-loosening capability than single thread locking, effectively suppressing the risk of slow retraction of the internal thread bearing housing 3 caused by pump body vibration. The detachable connection of the locking bolts ensures rigid fixation during operation, while allowing the bolts to be loosened and the internal thread bearing housing 3 to be rotated in the reverse direction to allow the main shaft 2 to be smoothly removed during maintenance or bearing replacement. It takes into account the flexibility of adjustment, the reliability of assembly, and the convenience of disassembly. The overall structure is simple and practical, enhancing the long-term operational stability and maintenance friendliness of the magnetic levitation bearing system.

[0046] A method for controlling the bearing structure of a high-efficiency magnetic levitation pump is characterized by the following step S1: rotating the internal thread bearing seat 3 and fine-tuning its depth of screwing into the pump housing 1 to adjust the air gap between the main shaft 2 and the external magnetic actuator, so that the main shaft 2 reaches the initial levitation state under the action of magnetic force.

[0047] Step S2: Start the external magnetic drive to drive the main shaft 2 to rotate at high speed. During the rotation, the radial swing of the main shaft 2 is limited by the cooperation between the flat keyway 21 of the main shaft 2 and the flat key in the pump housing 1.

[0048] Step S3: The sensing module 12 acquires the vibration or pressure status signal of the spindle 2 in real time and feeds the signal back to the PLC controller. The PLC controller adjusts the magnitude and phase of the electromagnetic force of the magnetic drive according to the feedback signal to maintain the magnetic levitation balance.

[0049] Step S4: When a power outage or magnetic drive failure occurs, the main shaft 2 loses its levitation force, falls instantly, and is purely mechanically supported by the tapered roller bearing 4 to prevent the main shaft 2 from making hard contact with the pump housing 1 and rubbing against the rotor.

[0050] Furthermore, in step S1, by rotating the internal thread bearing seat 3, the air gap between the spindle 2 and the external magnetic actuator is adjusted to between 0.5mm and 2.5mm, so that the spindle 2 is in the critical balance range between magnetic attraction and mechanical support. The levitation magnetic attraction force generated by the magnetic actuator on the spindle 2 has a non-linear inverse relationship with the size of the air gap. When the air gap is too large, the magnetic attraction force is insufficient to overcome the gravity of the spindle 2, resulting in levitation failure. When the air gap is too small, the magnetic attraction force increases sharply and may kill the spindle 2. The design of the 0.5mm to 2.5mm range is exactly located in the inflection point area between the steep and flat sections of the magnetic force curve. Within this range, the magnetic attraction force can just offset the gravity of the spindle and has a certain self-stabilizing margin. At the same time, the small gap mechanical support formed by the tapered roller bearing 4 and the inner side of the internal thread bearing seat 3 serves as an auxiliary limit, so that the spindle 2 will neither sink too much nor float too much under slight disturbance, forming a critical balance state in which the upward attraction of magnetic force and the downward limit of mechanical force counterbalance each other.

[0051] The continuous and precise control of the air gap is achieved through the stepless adjustment of the thread, which compensates for the deviation caused by machining and assembly tolerances. This ensures that each pump can find the optimal starting suspension working point. The reasonable range of 0.5mm to 2.5mm takes into account both magnetic efficiency and anti-disturbance ability, ensuring sufficient suspension stiffness while avoiding the risk of being sucked up. This allows the main shaft 2 to be in a critical state of pre-suspension before startup, which greatly reduces the impact and overshoot of magnetic control during startup and lays a reliable prerequisite for the high-speed and stable rotation of the subsequent step S2.

[0052] Furthermore, in step S3, when the sensing module 12 detects that the radial vibration amplitude exceeds the set threshold, the PLC controller adjusts the phase of the main magnetic field of the magnetic drive and changes the tangential torque of the electromagnetic field to counteract the radial eddy current of the main shaft 2. The sensing module 12 transmits the vibration signal collected in real time to the PLC controller through the signal line. The PLC controller calculates the frequency and amplitude of the vibration signal according to the built-in algorithm, identifies the direction and phase angle of the radial eddy current, and then outputs control commands to adjust the timing of the excitation current of the magnetic drive, so that the phase of the main magnetic field shifts. This phase change generates a tangential electromagnetic torque between the stator and the rotor that is opposite to the direction of the radial eddy current. This tangential torque acts on the radial direction of the main shaft 2, generating a reverse restoring force, thereby counteracting or weakening the radial eddy current of the main shaft 2 caused by fluid disturbance and magnetic field asymmetry, so that the main shaft 2 returns to a stable central suspension position.

[0053] The PLC controller suppresses eddy currents by actively adjusting the phase of the magnetic field rather than simply increasing or decreasing power. It has a fast response speed and low energy loss, and can accurately match the instantaneous frequency and phase of eddy currents to achieve dynamic reverse cancellation. Compared with methods that rely on mechanical damping or increase bearing stiffness, this method does not increase friction pairs, does not affect high-speed rotation efficiency, and does not require additional radial displacement sensors. Closed-loop control can be completed using the existing sensing module 12, which simplifies the system structure and reduces costs. It effectively improves the anti-disturbance capability and suspension stability of the magnetic levitation system under varying operating conditions.

[0054] Furthermore, the method also includes an overload protection step S5: when the sensing module 12 detects that the internal pressure of the pump body exceeds the design pressure limit, the PLC controller actively cuts off the power supply to the magnetic drive. The main shaft 2 is rapidly displaced backward by the fluid counterforce, and the end face of the tapered roller bearing 4 directly bears the ultimate axial load, forming a hard anti-reverse protection. The sensing module 12 continuously monitors the internal fluid pressure of the pump body. When the detected pressure value exceeds the preset design pressure limit in the PLC controller, the PLC controller immediately determines that the system is in an overload state. The pump activates a power-off command to cut off the power supply to the magnetic drive, causing the main shaft 2 to instantly lose its magnetic levitation support. At this time, the high-pressure fluid inside the pump generates a backward thrust on the impeller and the main shaft 2, pushing the main shaft 2 to move rapidly backward along the axial direction until the rear end of the main shaft 2 contacts the end face of the tapered roller bearing 4. This end face, with its large contact area and the unique axial bearing capacity of the double-row roller structure, directly bears the ultimate axial impact load from the main shaft 2, forming a hard anti-reverse mechanical limit, preventing the main shaft 2 from continuing to move backward and colliding with the rear end of the pump casing 1.

[0055] This overload protection relies entirely on a purely mechanical hard stop mechanism, requiring no additional hydraulic or pneumatic actuators. It has an extremely fast response speed and is unaffected by electromagnetic interference. The tapered roller bearing 4 has both axial limiting and impact absorption functions, serving multiple purposes. It effectively prevents the spindle 2 from impacting the pump housing 1 during overload, thus avoiding damage to the isolation sleeve or magnetic components. At the same time, the impact load generated by the hard stop is evenly distributed by the raceway on the end face of the bearing 4, avoiding stress concentration and protecting the critical mating surfaces of the pump housing 1 and the spindle 2. This significantly improves the overall machine's safety tolerance and lifespan under abnormal operating conditions.

[0056] Furthermore, the control method also includes equipment maintenance step S6: When it is necessary to disassemble the main shaft 2 to replace the bearing, the internal thread bearing seat 3 is rotated in the reverse direction, causing the main shaft 2 to be withdrawn from the pump housing 1 as a whole. During the withdrawal process, the distance between the main shaft 2 and the external magnetic drive increases, and the magnetic attraction weakens sharply until it breaks free from the magnetic constraint, thereby easily removing the entire rotor assembly. When it is necessary to disassemble the main shaft 2 to replace the tapered roller bearing 4 or other internal components, the operator rotates the internal thread bearing seat 3 in the reverse direction by engaging the transmission part 5. The rotational motion is converted into axial backward motion by utilizing the threaded transmission pair between the internal thread bearing seat 3 and the internal thread flange port 11 of the pump housing 1. The movement causes the internal thread bearing seat 3 to gradually rotate out of the pump housing 1. During this process, the main shaft 2 is withdrawn from the pump housing 1 along with the main shaft due to the clearance fit with the inner side of the internal thread bearing seat 3. As the main shaft 2 gradually moves outward, the axial distance between it and the external magnetic drive continuously increases. According to the inverse square law of magnetic force decay, the magnetic attraction force acting on the main shaft 2 weakens sharply. When the distance increases to above the critical point of magnetic binding, the main shaft 2 completely breaks away from the magnetic attraction and no longer bears the strong axial magnetic pull. Thus, the main shaft 2, together with the tapered roller bearing 4 and other integral rotor components, can be easily pulled out of the pump housing 1 by manpower or simple tools.

[0057] The reverse rotation of the internal thread bearing housing 3 achieves the dual effects of mechanical limit release and magnetic force weakening. It eliminates the need for special puller tools or hydraulic devices to counteract strong magnetic forces, avoiding the risks of magnetic component damage, isolation sleeve deformation, or bearing scratches caused by forced pulling during traditional disassembly. The entire process is safe, labor-saving, and controllable, significantly reducing maintenance downtime. At the same time, due to the smooth disassembly process, wear on the mating surfaces is minimal, ensuring the fitting accuracy and repeatability of the main shaft 2 and pump housing 1 after reassembly, significantly improving the maintenance efficiency and maintainability of the equipment.

[0058] Working Process: In the initial assembly and debugging stage, the operator rotates the internal thread bearing seat 3 by screwing the transmission part 5, and uses the threaded engagement with the internal thread flange port 11 of the pump housing 1 to fine-tune the screwing depth, precisely adjusting the air gap between the main shaft 2 and the external magnetic drive to the critical balance range of 0.5mm to 2.5mm. This allows the main shaft 2 to reach a pre-suspended state under the synergistic effect of magnetic attraction and the mechanical support of the inner gap of the tapered roller bearing 4 and the internal thread bearing seat 3. Subsequently, the internal thread bearing seat 3 is fixed and locked to the pump housing 1 by the locking bolt in the flange mounting hole 31. After the external magnetic drive is started to drive the main shaft 2 to suspend and rotate at high speed, the flat keyway 21 and the corresponding flat key locking strip 22 set inside the pump housing 1 form a clearance fit, constraining the main shaft 2 in the circumferential direction to limit its radial swing. At the same time, the sensing module 12 embedded in the rectangular protrusion space on the outer wall of the pump housing 1 collects vibration or pressure signals in real time and transmits them to the external PLC controller through the signal line. The C controller adjusts the magnitude and phase of the electromagnetic force of the magnetic actuator according to the feedback signal to dynamically maintain the magnetic levitation balance. When a power outage or magnetic drive failure occurs, the main shaft 2 instantly loses its levitation force and falls. The inner ring of the double-row tapered roller bearing 4 falls synchronously with the main shaft 2, and the roller converts the impact into rolling friction. The outer ring bears the load through the rear end of the pump housing 1 to avoid rubbing accidents. Under overload conditions, when the sensor module 12 detects that the internal pressure of the pump body exceeds the limit, the PLC controller actively cuts off the power supply of the magnetic actuator. The main shaft 2 is displaced backward by the fluid counter-thrust and the end face of the tapered roller bearing 4 bears the ultimate axial load to form a hard anti-reverse protection. When maintenance and disassembly are required, the internal thread bearing seat 3 is rotated in the opposite direction to make the main shaft 2 withdraw out of the pump housing 1. As the distance between the main shaft 2 and the external magnetic actuator increases, the magnetic attraction weakens sharply according to the inverse square law until it breaks free from the magnetic restraint. The entire rotor assembly, including the main shaft 2 and the tapered roller bearing 4, can be easily disassembled to complete the entire operation.

[0059] In the description of this invention, it should be understood that the terms "front and back", "left and right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or component 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 the invention.

[0060] Of course, those skilled in the art should understand that the term "a" should be understood as "at least one" or "one or more". That is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple. The term "a" should not be understood as a limitation on the quantity.

[0061] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art under the technical guidance of the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A high-efficiency magnetic levitation magnetic pump bearing structure, characterized in that: include The pump housing (1), main shaft (2), internal thread bearing seat (3) and tapered roller bearing (4) are provided. The main shaft (2) is connected through the pump housing (1), and one end of the main shaft (2) is provided with a flat keyway (21). The other end of the main shaft (2) is supported by the tapered roller bearing (4). One end of the pump housing (1) is provided with an internal thread flange port (11). The inner side of the internal thread bearing seat (3) is used to form a clearance fit with the main shaft (1), and the outer side of the internal thread bearing seat (3) is provided with a screw-in transmission part (5). The outer wall of the pump housing (1) is provided with a sensing module (12).

2. The high-efficiency magnetic levitation magnetic pump bearing structure according to claim 1, characterized in that, The tapered roller bearing (4) is a double-row tapered roller bearing, and the outer ring of the tapered roller bearing (4) is fixed to the rear end of the pump housing (1), and the inner ring is fitted and locked to the main shaft (2).

3. The high-efficiency magnetic levitation magnetic pump bearing structure according to claim 1, characterized in that, The keyway (21) is a semi-open keyway, and the length of the keyway (21) extends to one end of the main shaft (2) near the internal thread bearing seat (3); the pump housing (1) is provided with a keyway locking strip (22) that is clearance-fitted with the keyway (21).

4. The high-efficiency magnetic levitation magnetic pump bearing structure according to claim 1, characterized in that, The sensing module (12) is a pressure sensing module or an acceleration vibration sensing module, and the sensing module (12) is embedded in the rectangular protrusion space on the outer wall of the pump housing (1). The sensing module (12) is connected to a signal line, which is electrically connected to an external PLC controller. The PLC controller is electrically connected to a magnetic drive.

5. The high-efficiency magnetic levitation magnetic pump bearing structure according to claim 1, characterized in that, The outer periphery of the internal thread bearing housing (3) is provided with flange mounting holes (31) evenly distributed along the circumference. The flange mounting holes (31) are provided with locking bolts, and the locking bolts are fixedly connected to the pump housing (1) through the flange mounting holes (31).

6. A method for controlling the bearings of a high-efficiency magnetic levitation pump employing all the structures of claims 1-5, characterized in that, The process includes step S1: rotating the internal thread bearing seat (3) and fine-tuning its depth into the pump housing (1) to adjust the air gap between the main shaft (2) and the external magnetic actuator, so that the main shaft (2) reaches the initial suspension state under the action of magnetic force. Step S2: Start the external magnetic drive to drive the main shaft (2) to rotate at high speed. During the rotation, the radial swing of the main shaft (2) is limited by the cooperation between the keyway (21) of the main shaft (2) and the key in the pump housing (1). Step S3: The sensing module (12) acquires the vibration or pressure status signal of the spindle (2) in real time and feeds the signal back to the PLC controller. The PLC controller adjusts the magnitude and phase of the electromagnetic force of the magnetic drive according to the feedback signal to maintain the magnetic levitation balance. Step S4: When a power outage or magnetic drive failure occurs, the main shaft (2) loses its levitation force, falls instantly, and is purely mechanically supported by the tapered roller bearing (4) to prevent the main shaft (2) from making hard contact with the pump housing (1) and rubbing against the rotor.

7. The control method for a high-efficiency magnetic levitation magnetic pump bearing structure according to claim 6, characterized in that, In step S1, by rotating the internal thread bearing seat (3), the air gap between the spindle (2) and the external magnetic drive is adjusted to between 0.5mm and 2.5mm, so that the spindle (2) is in the critical balance range between magnetic attraction and mechanical support.

8. The control method for a high-efficiency magnetic levitation magnetic pump bearing structure according to claim 6, characterized in that, In step S3, when the sensing module (12) detects that the radial vibration amplitude exceeds the set threshold, the PLC controller adjusts the phase of the main magnetic field of the magnetic drive and changes the tangential torque of the electromagnetic field to counteract the radial eddy of the main shaft (2).

9. The control method for a high-efficiency magnetic levitation magnetic pump bearing structure according to claim 6, characterized in that, The method also includes an overload protection step S5: when the sensing module (12) detects that the internal pressure of the pump body exceeds the design pressure limit, the PLC controller actively cuts off the power supply of the magnetic drive, the main shaft (2) is rapidly displaced backward by the fluid counter-thrust, and the end face of the tapered roller bearing (4) directly bears the ultimate axial load, forming a hard anti-reverse protection.

10. The control method for a high-efficiency magnetic levitation magnetic pump bearing structure according to claim 6, characterized in that, The control method also includes equipment maintenance step S6: when it is necessary to disassemble the main shaft (2) to replace the bearing, rotate the internal thread bearing seat (3) in the opposite direction to make the main shaft (2) move out of the pump housing (1) as a whole. During the withdrawal process, the distance between the main shaft (2) and the external magnetic drive increases, and the magnetic attraction weakens sharply until it breaks away from the magnetic restraint, so as to easily remove the whole rotor assembly.

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