Magnetic levitation blood pump

Abstract

The application is a magnetic suspension blood pump with high integration, small magnetic field coupling degree and high regulation precision, comprising a pump shell, an impeller, a motor unit and a magnetic suspension unit, the magnetic interaction force between the electromagnet assembly and the suspension magnet assembly and the magnetic interaction force between the motor stator assembly and the motor rotor magnet jointly maintain the axial suspension state of the impeller, and the repulsion of the static magnetic ring array and the dynamic magnetic ring array maintains the radial suspension state of the impeller. The magnetic suspension unit and the motor unit are separately arranged at the upper and lower ends of the impeller, the distance between the two is enlarged in space, the magnetic coupling effect between the magnetic suspension unit and the motor unit is greatly reduced, the two are independently controlled, the control difficulty is significantly reduced, and the stability of the system is improved. The special structure design improves the space utilization, reduces the volume of the pump body, disperses the heat source, reduces the heat dissipation pressure, the bias magnetic field provided by the suspension magnet provides the open-loop magnetic force in the axial direction, greatly reduces the closed-loop control force provided by the electromagnet assembly, and achieves the purpose of energy saving and consumption reduction.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a magnetic levitation blood pump. BACKGROUND

[0002] Heart failure, in short, heart failure, is due to the contraction and / or diastolic function of the heart, and (or) the heart can not fully discharge the volume of blood back to the heart, leading to venous system blood stasis, and arterial system blood perfusion is insufficient, thereby causing heart failure syndrome. Artificial heart as a pump blood function for making up and replacing heart, provides a new medical means for heart failure patients. Magnetic levitation blood pump as the third generation of artificial heart, implanted at the apex of the heart, through the magnetic levitation technology makes the impeller suspended in the pump cavity, to eliminate mechanical wear and can effectively transport blood, because of its small size, good blood compatibility and excellent characteristics and has wide application prospect. In view of the use environment of magnetic levitation blood pump, under the premise of meeting the function, how to make the blood pump have the characteristics of high integration and small magnetic field coupling degree is the key technical problem that the technical personnel in the field always pay attention to. SUMMARY

[0003] The purpose of the present application is to provide a magnetic levitation blood pump with high integration, small magnetic field coupling degree and high control precision.

[0004] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows: a magnetic levitation blood pump, comprising a pump shell, a magnetic levitation type dynamic positioning of the impeller is positioned in the center area of the pump shell cavity and can rotate around the central axis of the pump shell, so as to suck blood from the inlet of the pump shell and discharge from the outlet;

[0005] The motor unit is an axial permanent magnet synchronous motor structure, comprising a motor stator assembly and a motor rotor magnet arranged on the impeller, and the two are arranged correspondingly in the axial direction. The motor stator assembly provides a rotating magnetic field acting on the motor rotor, which generates a rotating torque to drive the impeller to rotate;

[0006] The magnetic suspension unit comprises an electromagnet assembly and a suspension magnet assembly arranged on the impeller, and the two are correspondingly arranged in the axial direction, and a static magnetic ring array and a dynamic magnetic ring array arranged in the impeller, and the two are correspondingly arranged in the radial direction. The magnetic force between the electromagnet assembly and the suspension magnet assembly and the magnetic force between the motor stator assembly and the rotor magnet jointly maintain the axial suspension state of the impeller. The repulsion between the static magnetic ring array and the dynamic magnetic ring array maintains the radial suspension state of the impeller.

[0007] The magnetic suspension unit and the motor unit are separately arranged in the center area of the pump shell cavity in the upper and lower parts of the impeller. The impeller comprises an upper plate, a lower plate and a middle blade. The suspension magnet assembly is embedded in the upper plate, and the motor rotor magnet is embedded in the lower plate.

[0008] Further, the electromagnet assembly comprises a plurality of magnetic suspension cores arranged uniformly in the circumferential direction, the magnetic suspension core is in the structure of U-shaped cross section with the opening facing the impeller, comprising a bottom plate, and outer side plates and inner side plates located on the two sides of the bottom plate in the radial direction, the end of the outer side plate and the inner side plate is designed as a trapezoid, and the magnetic suspension coil is wound on the bottom plate.

[0009] Further, the suspension magnet assembly comprises a radially arranged outer annular magnet and an inner annular magnet, the lower end face of the outer side plate and the inner side plate is arranged correspondingly with the outer annular magnet and the inner annular magnet respectively, the upper end face of the outer annular magnet and the inner annular magnet is further provided with an outer magnetic conductive ring and an inner magnetic conductive ring respectively in the shape of right-angled trapezoid cross section, and the right-angled trapezoid cross sections of the two are arranged in mirror image symmetry.

[0010] Further, the plurality of magnetic suspension cores are fixed on the magnetic suspension PCB, and a plurality of position sensors are arranged on the lower plate face of the magnetic suspension PCB, one position sensor between every two adjacent magnetic suspension cores.

[0011] Further, the motor rotor magnet is embedded in the outer ring side of the lower plate, the electromagnet assembly is located on the upper plate end side of the impeller, the motor stator assembly is located on the lower plate end side of the impeller, and both have a gap.

[0012] Further, the inner cavity of the pump shell is divided into a first sealed chamber for installing the electromagnet assembly, a blood chamber for installing the impeller, and a second sealed chamber for installing the motor stator assembly from top to bottom by a partition plate, the middle part of the partition plate between the blood chamber and the second sealed chamber is provided with a flow guide part protruding towards the inside of the blood chamber, the static magnetic ring array is embedded in the flow guide part, the dynamic magnetic ring array is embedded in the inner ring side of the lower plate in the outer periphery of the flow guide part, and the dynamic magnetic ring array is located radially inside the motor rotor magnet and both are arranged in avoidance.

[0013] Further, the static magnetic ring array is composed of a plurality of magnetic rings stacked in the axial direction, the dynamic magnetic ring array is also composed of a plurality of magnetic rings stacked in the axial direction, the static magnetic ring array and the dynamic magnetic ring array are coaxially arranged in the axial direction, and the dynamic magnetic ring array is sleeved around the outer periphery of the flow guide part, forming the corresponding arrangement relationship of the static magnetic ring array and the dynamic magnetic ring array in the radial direction.

[0014] Further, the second sealed chamber is provided with a fixing column, the axis of the fixing column coincides with the axis of the blood pump, a main control PCB is arranged on the fixing column, and the motor stator assembly is arranged in the second sealed chamber above the main control PCB.

[0015] Further, the motor stator assembly comprises a plurality of stator cores arranged circumferentially and spaced apart, each stator core comprising a vertical plate, a top plate arranged on the top of the vertical plate, a stator coil arranged around the outer periphery of the vertical plate, and the top plate embedded in the partition plate between the blood cavity and the second sealed cavity and fixedly connected therewith, and a bottom of the stator core is provided with an annular stator yoke which fixes the plurality of stator cores into an integrated structure.

[0016] Further, the upper portion of the pump shell is provided with an inlet pipe, and an inner cavity of the inlet pipe is communicated with the blood cavity, and the outlet is arranged on the side wall of the blood cavity.

[0017] The above scheme has at least the following advantages:

[0018] The motor unit and the magnetic suspension unit are independently controlled, and the sandwich structure design greatly reduces the magnetic coupling effect between the motor unit and the magnetic suspension unit, thereby significantly reducing the control difficulty and improving the stability of the system.

[0019] The special structure design improves the space utilization rate, reduces the overall volume of the pump body, and disperses the heat source, thereby reducing the heat accumulation and reducing the heat dissipation pressure.

[0020] The bias magnetic field provided by the suspension magnet assembly provides an open-loop magnetic force in the axial direction, which greatly reduces the closed-loop control force provided by the electromagnet assembly, thereby achieving the purpose of energy saving and consumption reduction.

[0021] The electromagnet assembly with the special structure can more efficiently interact with the bias magnetic field when generating the active suspension force, thereby improving the suspension efficiency of the entire magnetic suspension system and enabling the blood pump to stably suspend the impeller with lower energy consumption.

[0022] The inner and outer annular magnets are aligned with the end faces of the electromagnet assembly, and when the impeller is deflected radially and axially offset under the action of an external force, the magnetic interaction force between the electromagnet assembly and the suspension magnet assembly can be adjusted by precisely adjusting the current of the electromagnet assembly at different circumferential positions, so as to adapt to the control requirements of different radial deflection and axial offset amounts. Since the magnetic field of the electromagnet assembly can be rapidly changed, the radial deflection and axial offset of the impeller can also be quickly responded.

[0023] The radial repulsion between the static magnetic ring array and the dynamic magnetic ring array provides passive radial damping, which can effectively suppress the radial offset caused by the external force, thereby realizing the stable suspension and rotation of the impeller.

[0024] The plurality of axially superimposed magnetic ring structures provide greater flexibility for the structural design of the blood pump, and the number, size, material and arrangement of the magnetic rings can be flexibly adjusted according to the specific size and performance requirements of the blood pump. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is an external view of the magnetic suspension blood pump.

[0026] Figure 2 Fig. 1 is a schematic diagram of the internal structure of the magnetic levitation blood pump;

[0027] Figure 3 Fig. 2 is a perspective view of the motor unit and the magnetic levitation unit of the magnetic levitation blood pump;

[0028] Figure 4 Fig. 3 is a schematic diagram of the cross section of the magnetic levitation blood pump; Figure 3

[0029] Figure 5 Fig. 4 is a schematic diagram of the force analysis of the impeller of the blood pump;

[0030] Figure 6 Fig. 5 is a schematic diagram of the magnetic field arrangement of the inner and outer magnetic ring arrays.

[0031] In the figure: 10-pump shell, 11-inlet, 12-outlet, 13-flow guide, 14-fixing column, 15-inlet pipe, 20-impeller, 21-upper plate, 22-lower plate, 23-vane, 30-motor unit, 31-motor stator assembly, 311-stator core, 311a-vertical plate, 311b-top plate, 312-stator coil, 313-stator yoke, 32-motor rotor magnet, 33-main control PCB board, 40-magnetic levitation unit, 41-electromagnet assembly, 411-magnetic levitation core, 411a-bottom plate, 411b-outer side plate, 411c-inner side plate, 412-magnetic levitation coil, 42-suspension magnet assembly, 421-outer annular magnet, 422-inner annular magnet, 423-outer magnetic conducting ring, 424-inner magnetic conducting ring, 43-static magnetic ring array, 44-dynamic magnetic ring array, 45-magnetic levitation PCB board, 46-position sensor. DETAILED DESCRIPTION

[0032] For the convenience of understanding, the terms "upper", "lower", "horizontal", "inner", "outer" and the like in the present disclosure indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present disclosure.

[0033] Since the magnetic levitation blood pump is implanted at the apex of the heart, the impeller is levitated in the pump cavity by the magnetic levitation technology to eliminate mechanical wear and effectively transport blood. Therefore, when designing the magnetic levitation blood pump, not only the biocompatibility and compact structure need to be considered, but also the mechanical properties (efficiency of driving force, stability of levitation force and mechanical stability), electromagnetic properties (magnetic field strength, electromagnetic compatibility and power consumption) and blood compatibility (materials, structure and flow field) need to be considered. The following will be further described in detail in combination with the drawings. Figure 1-Figure 5 The present disclosure is further described in detail. ​

[0034] A magnetic levitation blood pump, comprising a pump housing 10, an impeller 20 magnetically levitated and dynamically positioned in the central region of the chamber of the pump housing 10 and capable of rotating around the central axis of the pump housing 10 to suck blood from the inlet 11 of the pump housing 10 and discharge from the outlet 12; theoretically, the impeller 20 rotates around the central axis, and in fact, it is in a dynamic balance state, when the impeller 20 rotates and encounters external force to produce radial deflection and axial deviation, the accurate control of the plurality of electromagnets arranged in the circumferential direction is quickly responded through the control system, so that the impeller 20 quickly recovers to the balance state and continues to rotate around the central axis.

[0035] The motor unit 30 is an axial permanent magnet synchronous motor structure, comprising a motor stator assembly 31 and a motor rotor magnet 32 arranged on the impeller 20 and corresponding arranged in the axial direction, the motor stator assembly 31 provides a rotating magnetic field acting on the motor rotor magnet 32 to generate a rotating torque to drive the impeller 20 to rotate; this is the driving force for the rotation of the impeller 20, which can be adjusted by controlling the current vector parameters in the motor stator assembly 31 to adjust the rotating speed and torque of the impeller 20.

[0036] The magnetic levitation unit 40 comprises an electromagnet assembly 41 and a levitation magnet assembly 42 arranged on the impeller 20 and corresponding arranged in the axial direction, and a static magnetic ring array 43 and a dynamic magnetic ring array 44 arranged in the impeller 20 and corresponding arranged in the radial direction; the magnetic force between the electromagnet assembly 41 and the levitation magnet assembly 42 and the magnetic force between the stator assembly 31 and the motor rotor magnet 32 together maintain the axial levitation state of the impeller 20, and the repulsive force between the static magnetic ring array 43 and the dynamic magnetic ring array 44 maintains the radial levitation state of the impeller 20.

[0037] The force analysis of the impeller 20 will be analyzed below: Figure 5 In any cross section of the impeller 20 passing through the central axis, F1, F2, F3, F4 are the magnetic forces of the electromagnet assembly 41 to the levitation magnet assembly 42, F5, F6 are the magnetic forces of the motor stator assembly 31 to the motor rotor magnet 32, F7 and F ８ are the radial repulsive forces of the static magnetic ring array 43 to the dynamic magnetic ring array 44, the levitation magnet assembly 42, the motor rotor magnet 32 and the dynamic magnetic ring array 44 are all built-in in the impeller 20, forming a whole, wherein the self-gravity of the impeller 20 and the buoyancy of the blood to it are small in magnitude and can be ignored, so that the resultant force of F1+F2+F3+F4 and the resultant force of F5+F6 are balanced in the axial direction, the impeller 20 is in a stable levitation state in the axial direction, F ７ and F ８ provide damping force in the radial direction of the impeller 20, and the impeller 20 is in a stable levitation state in the radial direction. In summary, the impeller 20 is in a dynamic balance in the axial and radial directions, thereby ensuring the stable levitation of the impeller 20.

[0038] The magnetic suspension unit 40 and the motor unit 30 are separately arranged in the central region of the pump shell 10 cavity at the upper and lower parts of the impeller 20, the impeller 20 comprises an upper plate 21, a lower plate 22 and a middle blade 23, the suspension magnet assembly 42 is embedded in the upper plate 21, and the motor rotor magnet 32 is embedded in the lower plate 22.

[0039] The motor unit 30 and the magnetic suspension unit 40 in the application are separately controlled, the magnetic suspension unit 40 and the motor unit 30 are separately arranged in the central region of the pump shell 10 cavity at the upper and lower parts of the impeller 20, the sandwich structure design greatly reduces the magnetic coupling effect between the motor unit 30 and the magnetic suspension unit 40, can significantly reduce the control difficulty, improve the stability of the system, can further improve the space utilization, reduce the overall volume of the pump body, at the same time, the heat source is dispersed, not easy to accumulate heat, reduces the heat dissipation pressure.

[0040] Meanwhile, the suspension magnet assembly 42 can generate a bias magnetic field as a permanent magnet. The presence of the bias magnetic field has at least the following beneficial effects: (1) The impeller 20 needs to be suspended in the center area of the chamber of the pump shell 10 to realize contactless rotation, eliminating mechanical wear and thus greatly reducing damage to blood. The bias magnetic field provided by the suspension magnet provides the impeller 20 with an open-loop magnetic force in the axial direction, so that the closed-loop control force required for the electromagnet assembly 41 to maintain the suspension of the impeller 20 is greatly reduced. Without the bias magnetic field, the electromagnet assembly 41 needs to consume more power to generate a large enough magnetic force to overcome the gravity of the impeller 20, the magnetic attraction force of the motor unit, and other forces. With the bias magnetic field, the electromagnet assembly 41 only needs to fine-tune on this basis, greatly reducing the demand for magnetic flux of the electromagnet assembly 41, achieving the purpose of energy saving and consumption reduction. (2) The bias magnetic field provides a stable starting point for the suspension of the impeller 20, so that the impeller 20 obtains an open-loop magnetic force without active control, laying a foundation for subsequent precise suspension control by the electromagnet assembly 41 to eliminate radial deflection and axial deviation of the impeller caused by external forces. (3) The bias magnetic field forms a stable magnetic flux distribution in the air gap through the high magnetic energy product of the suspension magnet assembly 42, providing a basic support force for the impeller 20; when the impeller 20 deviates from the equilibrium position, the superposition or cancellation effect of the bias magnetic field and the control magnetic field (such as the difference in main air gap magnetic flux density) can quickly generate a restoring force, enhancing the carrying capacity and dynamic stability of the system. (4) Although the bias magnetic field is open-loop and unstable, it can provide position information for the suspension of the impeller 20. When the blood pump is disturbed by external vibrations, blood flow changes, and other factors during operation, the magnetic flux of the bias magnetic field passing through the position sensor will change, causing the voltage signal output by the position sensor to change relative to the voltage signal output at the equilibrium position. After a series of calculations in the main control, the position change of the impeller 20 is obtained, and the corresponding adjustment signal is output. After being input to the electromagnet assembly 41 through the power amplifier, the purpose of active control is achieved, so that the impeller 20 can quickly recover to a stable suspended state, providing a stable passive signal for the control of the entire magnetic suspension blood pump system.

[0041] As a preferred scheme of the present application, the electromagnet assembly 41 comprises a plurality of magnetic suspension cores 411 arranged at uniform intervals in the circumferential direction, the magnetic suspension core 411 is of a U-shaped cross section and has an opening facing the impeller, comprising a bottom plate 411a, and an outer side plate 411b and an inner side plate 411c located on both sides of the bottom plate 411a in the radial direction, the end of the outer side plate 411b and the inner side plate 411c is designed as a trapezoid to reduce the area of the end face. Under the premise of not triggering the magnetic saturation effect of the magnetic suspension core 411, the area of the end face is appropriately reduced, the magnetic induction intensity passing through the end face is increased, and the magnetic force at the corresponding position is appropriately increased. The magnetic suspension coil 412 is wound on the bottom plate 411a, and the plurality of magnetic suspension cores 411 are arranged at intervals in the circumferential direction, and the arrangement direction of each magnetic suspension core 411 extends in the radial direction, the magnetic suspension coil 412 is wound on the bottom plate 411a, that is, the direction of the magnetic suspension coil 412 is radially wound, this winding method helps to make full use of space, avoids the mutual interference of adjacent coils, and has sufficient space to select thicker enameled copper wire for winding under the condition that the upper limit of the closed-loop control force meets the actual application, thereby reducing the resistance and unnecessary energy loss.

[0042] The suspension magnet assembly 42 comprises a radially arranged outer ring magnet 421 and an inner ring magnet 422, the lower end face of the outer side plate 411b and the inner side plate 411c is arranged corresponding to the outer ring magnet 421 and the inner ring magnet 422 respectively, and the upper end face of the outer ring magnet 421 and the inner ring magnet 422 is further provided with an outer magnetic conducting ring 423 and an inner magnetic conducting ring 424 with a right-angled trapezoidal cross section, and the right-angled trapezoidal cross sections of the two are mirror-symmetrically arranged. There are two purposes for this design, one is that the right-angled trapezoidal design has the same purpose as the trapezoidal design of the end of the outer side plate 411b and the inner side plate 411c, that is, to increase the magnetic induction intensity passing through the end face of the outer magnetic conducting ring 423 and the inner magnetic conducting ring 424, thereby increasing the magnetic force; the other purpose is to design symmetrically to as far as possible to pull apart the spacing of the upper end faces of the two trapezoids, thereby as far as possible to reduce the degree of coupling of the bias magnetic field. In summary, when the outer magnetic conducting ring 423 and the inner magnetic conducting ring 424 cooperate with the permanent magnet to form a bias magnetic field system, the design of the right-angled trapezoidal cross section can optimize the properties of the magnetic suspension system, the outer magnetic conducting ring 423 and the inner magnetic conducting ring 424 can guide the magnetic field lines, can better cooperate with the end of the magnetic suspension core 411, make the magnetic field distribution of the gap space corresponding to the end face of the magnetic suspension core 411 and the end face of the outer magnetic conducting ring 423 and the inner magnetic conducting ring 424 more concentrated, increase the magnetic force and reduce the magnetic leakage phenomenon under the condition of constant magnetic flux, and improve the utilization rate of the magnetic field. In this way, the electromagnet assembly 41 can more efficiently interact with the bias magnetic field when generating a closed-loop control force, thereby improving the suspension efficiency of the entire magnetic suspension system, and enabling the blood pump to stably suspend the impeller 20 with lower energy consumption.

[0043] If the impeller 20 is radially deflected and axially offset, the magnetic flux of the generated bias magnetic field in the core of the electromagnet assembly 41 of the outer annular magnet 421 and the inner annular magnet 422 will change, resulting in the bias magnetic field force being larger or smaller than the balance position, and the magnetic force generated by the bias magnetic field is in an open loop state and cannot be feedback adjusted. At this time, the current in the magnetic suspension coil 412 of each electromagnet assembly 41 needs to be actively adjusted to compensate for the bias magnetic field, and the impeller 20 is actively pulled back to the original balance position. By accurately adjusting the current size and direction of the electromagnet assembly 41, the magnetic force of the bias magnetic field is accurately compensated to adapt to different radial deflection and axial offset amounts and control requirements.

[0044] The plurality of magnetic suspension cores 411 are fixed on the magnetic suspension PCB 45, which fixes the plurality of magnetic suspension cores 411 together to ensure that each magnetic suspension core 411 is on the same circumference. The magnetic suspension core 411 is provided with a plurality of position sensors 46 on the lower plate surface of the magnetic suspension PCB 45, with one position sensor 46 arranged between each two adjacent magnetic suspension cores 411. The position sensor 46 collects the real-time position of the impeller 20, and the control unit adjusts the current of the corresponding magnetic suspension coil 412 according to the position signal to realize stable control of the closed-loop control force on the impeller 20 in the axial direction.

[0045] Further, the motor rotor magnet 32 is embedded on the outer ring side of the lower plate 22, the electromagnet assembly 41 is located on the end side of the upper plate 21 of the impeller 20, and the motor stator assembly 31 is located on the end side of the lower plate 22 of the impeller 20, and all have gaps. The motor unit 30 and the magnetic suspension unit 40 are separately arranged in the lower part and the upper part of the impeller. This sandwich structure design can as much as possible separate the distance between the motor unit 30 and the magnetic suspension unit 40 in a limited space, greatly reduce the magnetic coupling effect between the motor unit 30 and the magnetic suspension unit 40, significantly reduce the control difficulty, improve the stability of the system, further improve the space utilization rate, reduce the overall volume of the pump body, and disperse the heat source, not easy to accumulate heat, reduce the heat dissipation pressure.

[0046] The inner cavity of the pump shell 10 is divided into a first sealed chamber A for installing the electromagnet assembly 41, a blood chamber B for installing the impeller 20, and a second sealed chamber C for installing the motor stator assembly 31 from top to bottom by a partition plate. The middle part of the partition plate between the blood chamber B and the second sealed chamber C is provided with a flow guide part 13 protruding towards the inside of the blood chamber C. The static magnetic ring array 43 is embedded in the flow guide part 13, and the dynamic magnetic ring array 44 is embedded on the inner ring side of the lower plate 22 outside the periphery of the flow guide part 13. The provision of the flow guide part 13 serves to install the static magnetic ring array 43 and also to guide the blood flow, thereby increasing the lift. The pump cavity is divided into the first sealed chamber A, the blood chamber B, and the second sealed chamber C by the partition plate, so that the overall structure is compact, the space is fully utilized, and the volume of the entire blood pump is further reduced. The first sealed chamber A, the second sealed chamber C, and the blood chamber B are isolated from each other, so that blood, impurities, etc. cannot enter the sealed chambers, and only the magnetic field can pass through, thereby ensuring the stability of the performance of the motor stator assembly 31 and the electromagnet assembly 41. The motor rotor magnet 32 in the impeller 20, the suspension magnet assembly 42, and the dynamic magnetic ring array 44 are all embedded inside the impeller 20 and do not directly contact the blood in the blood chamber B, thereby avoiding corrosion of the blood on the magnets. The dynamic magnetic ring array 44 is located radially inside the motor rotor magnet 32 and is arranged to avoid each other, thereby reasonably utilizing the space of the lower plate 22 and further reducing the volume and weight of the entire blood pump.

[0047] Preferably, the static magnetic ring array 43 is composed of a plurality of magnetic rings stacked axially, and the dynamic magnetic ring array 44 is also composed of a plurality of magnetic rings stacked axially. The static magnetic ring array 43 and the dynamic magnetic ring array 44 are coaxially arranged in the axial direction, and the dynamic magnetic ring array 44 is sleeved around the periphery of the flow guide part 13, forming a corresponding arrangement of the static magnetic ring array 43 and the dynamic magnetic ring array 44 in the radial direction. In combination with the magnetic field distribution, the static magnetic ring array 43 and the dynamic magnetic ring array 44 can provide radial damping force, so that the position of the impeller 20 in the radial direction remains relatively balanced. Figure 6 The structure of the plurality of axially stacked magnetic rings provides greater flexibility for the structural design of the blood pump, and the number, size, and arrangement of the magnetic rings can be flexibly adjusted according to the specific size and performance requirements of the blood pump.

[0048] In order to fix the motor stator assembly 31, the second sealed chamber C is provided with a fixing column 14, the axis of the fixing column 14 coincides with the axis of the blood pump, and the fixing column 14 is provided with a main control PCB 33. The motor stator assembly 31 is arranged in the second sealed chamber C above the main control PCB 33, and the motor stator assembly 31 is fixed by the main control PCB 33 and the fixing column 14, thereby ensuring the stability of the position of the motor stator assembly 31.

[0049] Specifically, the motor stator assembly 31 comprises a plurality of stator cores 311 arranged circumferentially and spaced apart, each stator core 311 comprising a vertical plate 311a, a top plate 311b arranged on the top of the vertical plate 311a, a stator coil 312 arranged around the outer periphery of the vertical plate 311a, the top plate 311b embedded in the partition plate between the blood cavity B and the second sealing chamber C and fixedly connected, and a bottom of the stator core 311 provided with an annular stator yoke 313, the stator yoke 313 fixing the plurality of stator cores 311 into an integrated structure. The lower part of the stator core 311 is fixed with the main control PCB 33, and the upper part is fixed with the partition plate, which can be regarded as both ends fixed on the pump shell 10, stable and firm in position.

[0050] Further, the upper part of the pump shell 10 is provided with an inlet pipe 15, the inner cavity of the inlet pipe 15 communicates with the blood cavity B, and the outlet 12 is arranged on the side wall of the blood cavity B. The inlet pipe 15 is an elongated tubular, used for implanting in the ventricle from the apex, and the outlet 12 is connected with a connecting pipe. When the blood pump is in operation, the blood in the ventricle enters the blood cavity B from the inner cavity of the inlet pipe 15, and is pumped to the target position from the outlet 12, so as to achieve the purpose of assisting the heart to pump blood.

[0051] It should be noted that the above describes some embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the schemes or steps recited in the claims can be executed in an order different from that described in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific sequence or continuous sequence shown to achieve the desired results. In some embodiments, multi-task processing and parallel processing are possible or can be advantageous.

Claims

1. A magnetic levitation blood pump, characterized in that: The pump comprises a pump housing (10), an impeller (20) dynamically positioned in a central area of ​​a chamber of the pump housing (10) in a magnetically suspended manner and capable of rotating around a central axis of the pump housing (10) to draw blood from an inlet (11) of the pump housing (10) and discharge blood from an outlet (12); The motor unit (30) is an axial permanent magnet synchronous motor structure, comprising a motor stator assembly (31) and a motor rotor magnet (32) disposed in the impeller (20), and the two are arranged correspondingly in the axial direction. The motor stator assembly (31) provides a rotating magnetic field acting on the motor rotor magnet (32), generating a rotational torque, thereby driving the impeller (20) to rotate. A magnetic suspension unit (40) comprises an electromagnet assembly (41) and a suspension magnet assembly (42) disposed on an impeller (20), the two being arranged in correspondence in the axial direction, and a static magnetic ring array (43) and a dynamic magnetic ring array (44) disposed in the impeller (20), the two being arranged in correspondence in the radial direction; the magnetic force between the electromagnet assembly (41) and the suspension magnet assembly (42) and the magnetic force between the motor stator assembly (31) and the motor rotor magnet (32) jointly maintain the axial suspension state of the impeller (20), and the repulsive force between the static magnetic ring array (43) and the dynamic magnetic ring array (44) maintains the radial suspension state of the impeller (20); The magnetic suspension unit (40) and the motor unit (30) are respectively disposed in the central area of ​​the pump casing (10) chamber above and below the impeller (20); the impeller (20) includes an upper plate (21), a lower plate (22), and blades (23) in the middle; the suspension magnet assembly (42) is embedded in the upper plate (21), and the motor rotor magnet (32) is embedded in the lower plate (22); The electromagnet assembly (41) comprises a plurality of magnetic levitation cores (411) uniformly spaced along the circumferential direction. The magnetic levitation core (411) is a structure having a U-shaped cross section and an opening facing the impeller, comprising a bottom plate (411a), and an outer plate (411b) and an inner plate (411c) located radially outside and inside the bottom plate (411a). The ends of the outer plate (411b) and the inner plate (411c) are designed to be trapezoidal. The magnetic levitation coil (412) is wound on the bottom plate (411a). The suspension magnet assembly (42) comprises an outer annular magnet (421) and an inner annular magnet (422) arranged radially, the lower end surfaces of the outer plate (411b) and the inner plate (411c) being arranged corresponding to the outer annular magnet (421) and the inner annular magnet (422), respectively, and the upper end surfaces of the outer annular magnet (421) and the inner annular magnet (422) are further provided with an outer magnetic conductive ring (423) and an inner magnetic conductive ring (424) having a right-angled trapezoidal cross section, respectively, and the right-angled trapezoidal cross sections of the two are arranged in mirror symmetry.

2. The magnetic levitation blood pump according to claim 1, characterized in that: A plurality of magnetic suspension iron cores (411) are fixed on a magnetic suspension PCB board (45); a plurality of position sensors (46) are provided on the lower surface of the magnetic suspension PCB board (45); and one position sensor (46) is provided between each of two adjacent magnetic suspension iron cores (411).

3. The magnetic levitation blood pump according to claim 1, characterized in that: The motor rotor magnet (32) is embedded in the outer ring side of the lower plate (22), the electromagnet assembly (41) is located on the end side of the upper plate (21) of the impeller (20), and the motor stator assembly (31) is located on the end side of the lower plate (22) of the impeller (20), and both have gaps.

4. The magnetic levitation blood pump according to claim 3, characterized in that: The inner cavity of the pump housing (10) is divided by a partition into a first sealed chamber (A) for installing the electromagnet assembly (41), a blood chamber (B) for installing the impeller (20), and a second sealed chamber (C) for installing the motor stator assembly (31) from top to bottom. A guide portion (13) protruding toward the inside of the blood chamber (B) is provided in the middle of the partition between the blood chamber (B) and the second sealed chamber (C). The static magnetic ring array (43) is embedded in the guide portion (13), and the dynamic magnetic ring array (44) is embedded in the inner ring side of the lower plate (22) on the outer periphery of the guide portion (13). The dynamic magnetic ring array (44) is located radially inward of the motor rotor magnet (32) and the two are arranged to avoid each other.

5. The magnetic levitation blood pump according to claim 4, characterized in that: The static magnetic ring array (43) is composed of a plurality of magnetic rings stacked axially, and the dynamic magnetic ring array (44) is also composed of a plurality of magnetic rings stacked axially. The static magnetic ring array (43) and the dynamic magnetic ring array (44) are coaxially arranged in the axial direction, and the dynamic magnetic ring array (44) is surrounded by the outer periphery of the guide portion (13), forming a relationship in which the static magnetic ring array (43) and the dynamic magnetic ring array (44) are arranged correspondingly in the radial direction.

6. The magnetic levitation blood pump according to claim 4, characterized in that: A fixed column (14) is provided in the second sealed chamber (C), the axis of the fixed column (14) coincides with the axis of the blood pump, a main control PCB board (33) is provided on the fixed column (14), and the motor stator assembly (31) is provided in the second sealed chamber (C) above the main control PCB board (33).

7. The magnetic levitation blood pump according to claim 4, characterized in that: The motor stator assembly (31) includes a plurality of stator cores (311) arranged at intervals in the circumferential direction. The stator core (311) includes a vertical plate (311a). A top plate (311b) is provided on the top of the vertical plate (311a). The stator coil (312) is wound around the outer circumference of the vertical plate (311a). The top plate (311b) is embedded in the partition between the blood chamber (B) and the second sealed chamber (C) to form a fixed connection. An annular stator yoke (313) is provided at the bottom of the stator core (311). The stator yoke (313) fixes the plurality of stator cores (311) into an integrated structure.

8. The magnetic levitation blood pump according to claim 4, characterized in that: An inlet pipe (15) is provided on the upper portion of the pump housing (10), the inner cavity of the inlet pipe (15) is communicated with the blood cavity (B), and the outlet (12) is provided on the side wall of the blood cavity (B).

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