Implantable magnetic suspension blood pump

Abstract

According to the implantable magnetic suspension blood pump, an impeller is suspended in a containing cavity of a pump shell and can rotate around the central axis of the pump shell, and a motor comprises a motor stator assembly arranged in the pump shell and a rotor magnet array arranged on the impeller; the magnetic suspension device comprises an electromagnet arranged in the pump shell and a suspension magnet assembly arranged on the impeller. Active electromagnetic suspension force provided by the electromagnet and passive permanent magnet bias suspension force provided by the suspension magnet assembly act together to enable the impeller to maintain a balanced suspension state in the axial direction and the radial direction. The motor and the magnetic suspension device are independently controlled to effectively reduce the negative influence of low signal detection accuracy caused by magnetic field coupling, and the hybrid magnetic suspension structure reduces the power consumption of the magnetic suspension device; the arrangement mode of the electromagnet and the motor stator assembly enables the whole structure to be compact, and the size and the weight of the blood pump are reduced; the suspension position of the permanent magnet is accurately controlled by accurately controlling the gap and the position relation between the electromagnet and the suspension magnet assembly.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an implantable magnetic suspension blood pump. Background Art

[0002] Heart failure, also known as HF, refers to the inability to fully discharge venous blood from the heart due to the impairment of the heart's contractile and / or diastolic functions, resulting in blood congestion in the venous system and insufficient blood perfusion in the arterial system, which in turn causes cardiac circulatory disorder syndrome. Artificial hearts, used to compensate for and replace the heart's pumping function, provide a new medical treatment for patients with heart failure. As the third-generation artificial heart, magnetic levitation blood pumps are widely used due to their small size and good blood compatibility. In the prior art, in magnetic levitation blood pumps, the motor magnetic field and the magnetic levitation magnetic field will be coupled, which will cause the control system to have greater interference when detecting the rotor position signal, and there may be a greater risk of loss of control; at the same time, the magnetic force that controls the suspension of the rotor is completely provided by the electromagnetic coil, which will greatly increase the energy consumption of the control system. Summary of the invention

[0003] The object of the present invention is to provide an implantable magnetically suspended blood pump which has a compact structure and can realize axial-radial decoupling regulation.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an implantable magnetic suspension blood pump structure, comprising: A pump housing having a receiving chamber and an inlet and an outlet for guiding and discharging blood; An impeller, which is dynamically positioned in a central region of the pump housing chamber by magnetic suspension and is capable of rotating about a central axis of the pump housing to draw blood from the inlet and discharge blood from the outlet; The motor comprises a motor stator assembly disposed in the pump housing and a rotor magnet array disposed on the impeller, and the two are arranged in an axial direction, and the motor stator assembly provides a rotating magnetic field to drive the rotor magnet array to drive the impeller to rotate; The magnetic suspension device comprises an electromagnet disposed in the pump housing and a suspension magnet assembly disposed on the impeller, and the two are arranged in a radial direction, and the active electromagnetic suspension force provided by the electromagnet and the passive permanent magnetic bias suspension force provided by the suspension magnet assembly work together to maintain the impeller in a balanced suspension state in the axial and radial directions; In the radial direction, the magnetic suspension device is generally located on the inner side of the motor.

[0005] Furthermore, the impeller includes an impeller body and a tube column arranged on the impeller body, the outer diameter of the tube column is smaller than the outer diameter of the impeller body, a plurality of closed streamlined blades are arranged on the impeller body, the blades and the upper and lower panels of the impeller form a main flow channel, the inner cavity of the tube column is connected to the main flow channel, the rotor magnet array is arranged on the impeller body away from the inlet side, the motor stator assembly is arranged on the outer periphery of the tube column and is arranged axially corresponding to the rotor magnet array, the suspension magnet assembly is arranged inside the tube column, the electromagnet is located in the inner cavity of the tube column and is arranged radially corresponding to the suspension magnet assembly.

[0006] Furthermore, the pump casing includes a bottom shell, a middle shell and an upper shell. The bottom shell and the middle shell are connected to form a sealed chamber for installing a motor stator assembly and an electromagnet. The middle shell and the upper shell are connected to form a blood cavity for installing an impeller. A guide portion protruding toward the blood cavity is provided in the middle of the middle shell. The outer periphery of the guide portion forms a groove for embedding a pipe column. The electromagnet is arranged in the inner cavity of the guide portion.

[0007] Furthermore, a positioning column is extended downward from the inner cavity of the guide part, and the positioning column is fixedly connected to the bottom shell. The electromagnet includes 4-pole, 6-pole and 8-pole magnetic levitation cores arranged at intervals along the circumference of the positioning column, and are arranged in one group at every 90°, 60° and 45° respectively, and are made of 0.2mm silicon steel sheet stacks to reduce eddy current losses. Each group of magnetic levitation cores is a structure with a U-shaped cross-section and an opening radially outward, including a bottom plate, and an upper side plate and a lower side plate located on both sides of the bottom plate. The magnetic levitation coil is wound around the outer periphery of the lower side plate, and a spacing sensor is arranged on the side of the upper side plate, corresponding to the symmetrical layout of the 4-pole, 6-pole and 8-pole magnetic levitation cores, and are arranged in one group at every 90°, 60° and 45 degrees respectively.

[0008] Furthermore, a fixed sleeve is sleeved on the positioning column, the bottom plate is fixed on the outer peripheral wall of the fixed sleeve, a spacing sensor PCB board is arranged on the top of the fixed sleeve, and the spacing sensor PCB board is clamped between the upper wall of the inner cavity of the guide part and the upper side plate.

[0009] Furthermore, the suspension magnet assembly includes an annular magnet embedded in the inner wall of the pipe column, and an upper magnetic ring and a lower magnetic ring arranged on the upper and lower end surfaces of the annular magnet, wherein the upper magnetic ring and the lower magnetic ring are arranged radially corresponding to the upper side plate and the lower side plate respectively.

[0010] Furthermore, the top of the guide portion protrudes to the top of the inner cavity of the impeller body and is less than or equal to 1 / 2 of the inner cavity of the impeller body. The top of the guide portion is a smooth conical surface. The gap between the tube column and the groove constitutes a secondary flow channel. After passing through the secondary flow channel, the blood is guided by the guide portion to the inner cavity of the impeller body and mixed with the blood in the inner cavity of the impeller body.

[0011] Furthermore, the motor stator assembly is arranged in a space surrounded by the outer periphery of the groove, the inner wall of the middle shell and the inner wall of the bottom shell, including a plurality of stator cores arranged at intervals along the circumferential direction, adopting a 3-pole and 6-pole symmetrical layout, arranged in a group every 120° and 60° respectively, and made of 0.2mm silicon steel sheet laminations to reduce eddy current losses. The stator core includes a vertical plate, a top plate is arranged on the top of the vertical plate, the stator coil is wound around the outer periphery of the vertical plate, the top plate is embedded in the middle shell and forms a fixed connection, a position sensor is arranged between every two adjacent top plates, the position sensor is fixed on the position sensor PCB, the rotor magnet array corresponds to the stator core layout on the radial circumference, an annular stator yoke is arranged at the bottom of the stator core, the stator yoke fixes the plurality of stator cores into an integrated structure, a main control PCB board is also arranged in the inner cavity of the annular stator yoke, and the main control PCB board is fixed on the positioning column.

[0012] Furthermore, a first auxiliary annular magnet is provided in the upper plate surface of the impeller body. The first auxiliary annular magnet is arranged opposite to the end surface of the second auxiliary annular magnet provided in the upper shell. The two are magnetically attracted to each other, thereby assisting the impeller to maintain a centered state.

[0013] Furthermore, a plurality of support columns are protruding upward from the bottom of the bottom shell, the tops of the support columns are in contact with the stator core and the magnetic levitation core to form a limiting fit, and a positioning groove is also provided at the bottom of the bottom shell, and the lower end of the positioning column is inserted into the positioning groove to form a limiting fit.

[0014] The above scheme has at least the following beneficial effects: The motor and magnetic levitation device are controlled separately, which effectively reduces the negative impact of low signal detection accuracy caused by magnetic field coupling and improves control accuracy and system stability. A hybrid magnetic levitation system that combines active electromagnetic control with a passive permanent magnet bias magnetic field is used. The bias magnetic field of the passive permanent magnet is used to provide a passive magnetic force, thereby reducing the power consumption of the magnetic levitation device. The electromagnet is arranged in the area where the inner cavity of the guide part is located, and the motor stator assembly is arranged around the outer periphery of the groove. The overall structure is compact, which reduces the size of the entire blood pump, reduces the weight, facilitates implantation in the human body, and improves wearing comfort. The special structural setting of the magnetic levitation device can achieve precise control of the impeller suspension position and state by precisely controlling the gap and position relationship between the electromagnet and the suspension magnet assembly, thereby avoiding hard friction between the impeller and the inner wall of the pump casing and improving the biocompatibility and stability of the blood pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is the appearance diagram of the magnetic levitation blood pump; Figure 2 is an axial cross-sectional view of the magnetic levitation blood pump; Figure 3is a front cross-sectional view of a magnetically suspended blood pump; Figure 4 Schematic diagram of the internal structure of the magnetic levitation blood pump. DETAILED DESCRIPTION

[0016] For ease of understanding, the terms "upper", "lower", "horizontal", "inside", "outside", etc. involved in the text indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0017] Since the magnetic suspension blood pump is implanted at the apex of the heart, the impeller is suspended in the pump cavity through magnetic suspension technology to reduce mechanical wear and effectively transport blood. Therefore, in its design, it is necessary to consider not only biocompatibility and structural compactness, but also its mechanical properties (high efficiency of driving force, stability of suspension force and mechanical stability), electromagnetic properties (magnetic field strength, electromagnetic compatibility and power consumption) and blood compatibility (materials, structure and flow field).

[0018] An implantable magnetic suspension blood pump structure, such as Figure 1-Figure 4 As shown, including: The pump housing 10 has a receiving chamber and an inlet 14 and an outlet 15 for guiding and discharging blood; the receiving chamber is used to accommodate an impeller 20, a motor 30 and a magnetic suspension device 40.

[0019] The impeller 20 is dynamically positioned in the center area of ​​the chamber of the pump housing 10 by magnetic suspension and can rotate around the central axis of the pump housing 10 to suck blood from the inlet 14 and discharge it from the outlet 15. In theory, the impeller 20 rotates around the central axis, but in fact it is in dynamic balance. When there is a tendency to tilt, the control system corrects it in time so that the impeller 20 rotates around the central axis as a whole.

[0020] The motor 30 includes a motor stator assembly 31 disposed in the pump housing 10 and a rotor magnet array 32 disposed on the impeller 20. The motor stator assembly 31 provides a rotating magnetic field to drive the rotor magnet array 32 to drive the impeller 20 to rotate. This is the driving force for the impeller 20 to rotate. The speed of the impeller 20 can be adjusted by controlling the current vector parameters in the motor stator assembly 31. The magnetic suspension device 40 includes an electromagnet 41 disposed in the pump housing 10 and a suspension magnet assembly 42 disposed on the impeller 20. The electromagnetic suspension force provided by the electromagnet 41 and the permanent magnetic suspension force provided by the suspension magnet assembly 42 work together to maintain the impeller 20 in a balanced suspension state in the axial and radial directions. By adjusting the magnitude and direction of the current in the electromagnet 41, the impeller 20 is stably suspended and always rotates around the central axis of the inner cavity of the pump housing 10. During the blood pumping process, the impeller 20 will not rub against the inner cavity of the pump housing 10, thereby reducing blood damage. When the electromagnet 41 is energized, a magnetic field is generated. This magnetic field interacts with the ferromagnetic material in the impeller 20 to generate an upward electromagnetic force. By controlling the current and magnetic field strength of the electromagnet 41, the magnitude and direction of this electromagnetic force can be accurately adjusted, thereby achieving the suspension of the impeller 20. In addition, the suspension magnet assembly 42 can provide a passive permanent magnet bias magnetic field and provide a passive magnetic suspension force, but the passive magnetic suspension force is in an open-loop state, and the electromagnet 41 is required to provide an actively adjusted magnetic field to balance the fluctuation of the passive magnetic suspension force to achieve a closed-loop control effect. In this way, the suspension force required for the impeller 20 to suspend is mainly provided by the permanent magnet bias magnetic field, and the electromagnet 41 only needs to provide an adjusted magnetic field, which greatly reduces the demand for the magnetic flux of the electromagnet 41 and achieves the purpose of energy saving and consumption reduction.

[0021] The magnetic levitation device 40 is located on the inner circle of the axis of the blood pump, and the motor 30 is located on the outer circle of the axis of the blood pump, that is, in physical space and in the radial direction, the magnetic levitation device 40 is located on the inner side of the motor 30 as a whole, that is, the motor stator assembly 31 and the rotor magnet array 32 are located on the outer periphery of the electromagnet 41 and the suspension magnet assembly 42 as a whole. The internal space of the pump housing 10 is reasonably utilized to arrange the magnetic levitation device 40 and the motor 30, thereby further reducing the volume and weight of the entire blood pump.

[0022] In summary, the motor 30 and the magnetic suspension device 40 in the present invention are controlled separately, and decoupling is achieved at the mechanical structure level, which effectively reduces the negative impact of low signal detection accuracy caused by magnetic field coupling, and improves the control accuracy and system stability. The magnetic suspension device 40 adopts a hybrid magnetic suspension that combines a passive permanent magnet bias magnetic field with active electromagnetic control, and uses the bias magnetic field of the annular permanent magnet to provide passive magnetic force, thereby reducing the power consumption of the magnetic suspension module.

[0023] like Figure 2 , Figure 3As shown, the impeller 20 includes an impeller body 21 and a pipe column 22 disposed on the impeller body 21. The outer diameter of the pipe column 22 is smaller than the outer diameter of the impeller body 21. A plurality of streamlined blades 211 are disposed on the impeller body 21. The blades 211 and the upper panel 212 and the lower panel 213 of the impeller form a main flow channel 214. The inner tube cavity of the pipe column 22 communicates with the main flow channel 214. The rotor magnet array 32 is disposed on the impeller body 21 on the side away from the inlet 14. The motor stator assembly 31 is disposed on the outer periphery of the pipe column 22 and is arranged axially corresponding to the rotor magnet array 32. The suspension magnet assembly 42 is disposed inside the pipe column 22. The electromagnet 41 is located in the inner cavity of the pipe column 22 and is arranged radially corresponding to the suspension magnet assembly 42. Since the outer diameter of the pipe column 22 is smaller than the outer diameter of the impeller body 21, the cross section of the entire impeller 20 is T-shaped, and installation space for the motor stator assembly 31 is reserved on both sides. In this way, the electromagnet 41 is arranged in the inner cavity area of ​​the tube column 22, and the motor stator assembly 31 is arranged around the outer periphery of the groove 122. The overall structure is compact, which reduces the size of the entire blood pump, facilitates implantation in the human body, and improves the performance of the blood pump.

[0024] like Figure 1 As shown, the pump housing 10 comprises a bottom housing 11, a middle housing 12 and an upper housing 13. The bottom housing 11 and the middle housing 12 are connected to form a sealed chamber A for installing a motor stator assembly 31 and an electromagnet 41. The middle housing 12 and the upper housing 13 are connected to form a blood chamber B for installing an impeller 20. A flow guide 121 is provided in the middle of the middle housing 12, which protrudes toward the blood chamber B. The outer periphery of the flow guide 121 forms a groove 122 for embedding the column 22. The electromagnet 41 is arranged in the inner cavity of the flow guide 121. The sealed chamber A and the blood chamber B are separated by a structure similar to a partition provided on the middle housing 12. The groove 122 and the flow guide 121 structure are obtained by designing the shape of the partition, and a space for installing the motor stator assembly 31 is also formed, so that the overall structure is compact, the occupied space is small, and the volume of the entire blood pump is further reduced. The sealed chamber A and the blood chamber B are isolated from each other, and no blood, impurities, etc. can enter the sealed chamber A. Only the magnetic field is allowed to pass through, thereby ensuring the stability of the performance of the motor stator assembly 31 and the electromagnet 41.

[0025] In order to install the electromagnet 41, a positioning column 123 is extended downward from the inner cavity of the guide part 121, and the positioning column 123 is fixedly connected to the bottom shell 11. The electromagnet 41 includes a plurality of magnetic levitation cores 411 arranged at intervals along the circumference of the positioning column 123. The magnetic levitation core 411 is a structure with a U-shaped cross-section and an opening radially outward, including a bottom plate 411a, and an upper side plate 411b and a lower side plate 411c located on both sides of the bottom plate 411a. The magnetic levitation coil 412 is wound around the outer periphery of the lower side plate 411c, and a spacing sensor 413 is provided on the side of the upper side plate 411b, which corresponds to the symmetrical layout of the 4-pole, 6-pole and 8-pole magnetic levitation cores, and is arranged in a group every 90°, 60° or 45° respectively. The impeller 20 is completely suspended in the blood cavity B by magnetic force, that is, centered in the axial direction. During the rotation of the impeller 20, if there is a tendency to deviate to one side, the magnetic force of the magnetic suspension coil 412 on the side is reduced by adjusting the current, and the magnetic force of the magnetic suspension coil 412 on the opposite side is increased. The two sides of the suspension magnet assembly 42 are subjected to magnetic forces of different magnitudes, and then the position is returned to the correct position. Through uninterrupted high-speed adjustment, the rotation axis of the impeller 20 is always within a very small vicinity around the central axis of the pump housing 10, ensuring that the impeller 20 will not contact the inner wall of the pump housing 10 when rotating, and has extremely high stability. In order to accurately control the position of the impeller 20, the magnetic suspension core 411 is arranged at circumferential intervals of the fixed column 123, and the number of magnetic suspension coils 412 and magnetic suspension cores 411 is arranged correspondingly. The number of magnetic suspension cores 411 is preferably not less than 4 and the number is an even number. By controlling the current vector parameters of the two magnetic suspension coils 412 on the same diagonal line, the impeller 20 is quickly returned to the correct position.

[0026] In order to ensure the reliability of the installation of the magnetic suspension core 411, a fixed sleeve 414 is sleeved on the positioning column 123, the bottom plate 411a is fixed on the outer peripheral wall of the fixed sleeve 414, and a spacing sensor PCB board 415 is arranged on the top of the fixed sleeve 414. The spacing sensor PCB board 415 is sandwiched between the guide part 121 and the upper side plate 411b. The spacing sensor 413 monitors the position of the impeller 20 in real time and transmits the position signal to the control unit. The control unit controls the current vector parameters of the magnetic suspension coil 412 and changes the suspension force to ensure that the position of the impeller 20 is centered.

[0027] As a preferred embodiment of the present invention, the suspension magnet assembly 42 includes an annular magnet 421 embedded in the inner wall of the pipe column 22, and an upper magnetic ring 422 and a lower magnetic ring 423 arranged on the upper and lower end surfaces of the annular magnet 421. The arrangement of the magnetic rings can optimize the properties of the magnetic suspension system, which is specifically manifested as follows: (1) enhancing the stability of the magnetic field: the magnetic rings can guide the magnetic field lines to make the magnetic field distribution more uniform, thereby improving the stability and reliability of the system; (2) improving the magnetic suspension efficiency: the magnetic rings can enhance the magnetic interaction between the annular permanent magnet and the magnetic suspension coil 412, thereby improving the suspension efficiency; (3) reducing eddy current losses: the magnetic rings can guide the magnetic rings to avoid certain specific areas, thereby reducing eddy current losses, and also have the effect of suppressing electromagnetic interference. The upper magnetic ring 422 and the lower magnetic ring 423 are arranged radially corresponding to the upper side plate 411b and the lower side plate 411c respectively, so that the annular magnet 421 is suspended between the magnetic suspension core 411, and the upper magnetic ring 422 and the lower magnetic ring 423 guide the magnetic field lines, so that the magnetic field is more evenly distributed between the electromagnet 41 and the annular magnet 421, which helps to improve the suspension efficiency and stability; the magnetic field lines are guided by the upper magnetic ring 422 and the lower magnetic ring 423 and can pass through the magnetic circuit along their route, thereby reducing leakage magnetic flux and improving the performance of the magnetic suspension system; because the end faces of the two are aligned in the radial direction, by accurately controlling the gap and positional relationship between the two, the precise control of the suspension position of the permanent magnet can be achieved, thereby improving the pumping efficiency and stability of the blood pump.

[0028] Furthermore, the top of the guide portion 121 protrudes to the top of the inner cavity of the impeller body 21 and the height of the top is less than or equal to 1 / 2 of the inner cavity of the impeller body 21. The top of the guide portion 121 is a smooth conical surface. The gap between the column 22 and the groove 122 constitutes a secondary flow channel C. After the blood passes through the secondary flow channel C, it is guided by the guide portion 121 to the inner cavity of the impeller body 21 and mixed with the blood in the inner cavity of the impeller body 21. Due to the existence of the pressure difference, the blood flow above will flow through the secondary channel C to form a secondary flow. The setting of the secondary flow channel C has at least the following beneficial effects: (1) Improve the blood flow state: The blood in the pump cavity is prone to blood flow disorder during the process of being transported from the blood inlet to the bleeding outlet. The secondary flow channel C can adjust the blood flow, reduce the generation of blood flow vortex, reduce the shear force on the blood in the vortex area, and prevent red blood cell rupture. (2) Prevent thrombosis: The secondary flow channel C can promote the blood to have a proper flow in every corner of the pump cavity, avoid blood retention in certain areas, and reduce the possibility of thrombosis. (3) Improve blood pump efficiency: The secondary flow channel C can adjust the blood inflow and outflow angles to a certain extent, allowing blood to enter and leave the impeller area more smoothly, thereby improving blood pumping efficiency. (4) Heat dissipation: The blood pump generates heat during the blood pumping process. When blood flows through the secondary flow channel C, it can absorb and take away the surrounding heat, preventing local overheating from causing damage to blood components.

[0029] Similarly, the motor stator assembly 31 is arranged in a space surrounded by the outer periphery of the groove 122, the inner wall of the middle shell 12 and the inner wall of the bottom shell 11, and includes a plurality of stator cores 311 arranged at intervals along the circumferential direction, the stator core 311 includes a vertical plate 311a, a top plate 311b is arranged on the top of the vertical plate 311a, the stator coil 312 is wound around the outer periphery of the vertical plate 311a, the top plate 311b is embedded in the middle shell 12 and is fixedly connected, and a position sensor 315 is arranged between every two adjacent top plates 311b, and the position sensor is fixed on the position sensor PCB 316, the rotor magnet array 32 is arranged in a pair of poles and two pairs of poles on the radial circumference, corresponding to the 3-pole or 6-pole layout of the stator core 311, wherein the end surface area of ​​the top plate 311b is larger than the cross-sectional area of ​​the vertical plate 311a, so when the top plate 311b corresponds to the rotor magnet array 32, the stator core 311 can more effectively capture and utilize the magnetic field generated by the permanent magnet, thereby improving the magnetic flux density and magnetic flux of the motor, which helps to enhance the electromagnetic torque and output power of the motor, so that the motor can output a greater torque or power under the same conditions. An annular stator yoke 313 is provided at the bottom of the stator core 311, and the stator yoke 313 fixes multiple stator cores 311 into an integrated structure. A main control PCB board 314 is also provided in the inner cavity of the annular stator yoke 313, and the main control PCB board 314 is fixed on the positioning column 123. The stator coil 312 is wound along the axial direction, which can reduce the occupied space and further reduce the volume and weight of the entire blood pump.

[0030] A first auxiliary annular magnet 23 is also provided in the upper plate surface of the impeller body 21. The first auxiliary annular magnet 23 is arranged opposite to the end surface of the second auxiliary annular magnet 16 provided in the upper shell 13. The two are magnetically attracted to each other, and the auxiliary impeller 20 is maintained in the center state. Since the end surfaces of the first auxiliary annular magnet 23 and the second auxiliary annular magnet 16 are arranged opposite to each other, when the impeller 20 tends to deviate, the component of the force between the two magnets in the horizontal direction will pull the impeller 20 radially inward to return its position, thereby improving the rotation stability of the impeller 20.

[0031] In order to fix the motor stator assembly 31 and the electromagnet 41, a plurality of support columns 17 are protruded upward from the bottom of the bottom shell 11, and the tops of the support columns 17 abut against the stator core 311 and the magnetic suspension core 411 to form a limit fit. A positioning groove 18 is also provided at the bottom of the bottom shell 11, and the lower end of the positioning column 123 is inserted into the positioning groove 18 to form a limit fit. This structure simplifies the assembly process of the blood pump and ensures the stability of the positions of the components inside the blood pump.

[0032] 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 recorded in the claims can be performed in an order different from that 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 order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

Claims

1. An implantable magnetic suspension blood pump, characterized in that: include: A pump housing (10) having a receiving cavity and an inlet (14) and an outlet (15) for guiding and discharging blood; An impeller (20) is dynamically positioned in a central area of ​​a chamber of the pump housing (10) in a magnetically suspended manner and is capable of rotating around a central axis of the pump housing (10) to draw blood from the inlet (14) and discharge blood from the outlet (15); The motor (30) comprises a motor stator assembly (31) disposed in the pump housing (10) and a rotor magnet array (32) disposed on the impeller (20), and the two are arranged in an axial direction, and the motor stator assembly (31) provides a rotating magnetic field to drive the rotor magnet array (32) to drive the impeller (20) to rotate; The magnetic suspension device (40) comprises an electromagnet (41) disposed in a pump housing (10) and a suspension magnet assembly (42) disposed on an impeller (20), the two being arranged in a radial direction, wherein an active electromagnetic suspension force provided by the electromagnet (41) and a passive permanent magnetic bias suspension force provided by the suspension magnet assembly (42) act together to maintain the impeller (20) in a balanced suspension state in the axial and radial directions; In the radial direction, the magnetic suspension device (40) is located as a whole on the inner side of the motor (30).

2. An implantable magnetic suspension blood pump according to claim 1, characterized in that: The impeller (20) comprises an impeller body (21) and a pipe column (22) arranged on the impeller body (21); the outer diameter of the pipe column (22) is smaller than the outer diameter of the impeller body (21); a plurality of streamlined blades (211) are arranged on the impeller body (21); the blades (211) and the upper panel (212) and the lower panel (213) form a main flow channel (214); the inner tube cavity of the pipe column (22) is connected to the main flow channel (214); the rotor magnet array (32) is arranged on the impeller body (21) on the side away from the inlet (14); the motor stator assembly (31) is arranged on the outer periphery of the pipe column (22) and is arranged corresponding to the rotor magnet array (32) in the axial direction; the suspension magnet assembly (42) is arranged inside the pipe column (22); the electromagnet (41) is located in the inner cavity of the pipe column (22) and is arranged corresponding to the suspension magnet assembly (42) in the radial direction.

3. An implantable magnetic suspension blood pump according to claim 2, characterized in that: The pump housing (10) comprises a bottom housing (11), a middle housing (12) and an upper housing (13); the bottom housing (11) and the middle housing (12) are butt-jointed to form a sealed chamber (A) for mounting a motor stator assembly (31) and an electromagnet (41); the middle housing (12) and the upper housing (13) are butt-jointed to form a blood chamber (B) for mounting an impeller (20); a flow guide (121) protruding toward the blood chamber (B) is provided in the middle of the middle housing (12); a groove (122) is formed on the outer periphery of the flow guide (121) for embedding a pipe column (22); and the electromagnet (41) is arranged in the inner cavity of the flow guide (121).

4. The implantable magnetic suspension blood pump according to claim 3, characterized in that: A positioning column (123) extends downward from the inner cavity of the flow guide portion (121); the positioning column (123) is fixedly connected to the bottom shell (11); the electromagnet (41) comprises a plurality of magnetic suspension cores (411) arranged at intervals along the circumference of the positioning column (123); each group of magnetic suspension cores (411) is a structure with a U-shaped cross section and an opening radially outward, comprising a bottom plate (411a), and an upper side plate (411b) and a lower side plate (411c) located on both sides of the bottom plate (411a); a magnetic suspension coil (412) is wound around the outer periphery of the lower side plate (411c); and a spacing sensor (413) is arranged on the side of the upper side plate (411b).

5. The implantable magnetic suspension blood pump according to claim 4, characterized in that: A fixed sleeve (414) is sleeved on the positioning column (123), the bottom plate (411a) is fixed on the outer peripheral wall of the fixed sleeve (414), a spacing sensor PCB board (415) is arranged on the top of the fixed sleeve (414), and the spacing sensor PCB board (415) is sandwiched between the upper wall of the inner cavity of the guide part (121) and the upper side plate (411b).

6. The implantable magnetic suspension blood pump according to claim 4, characterized in that: The suspension magnet assembly (42) comprises an annular magnet (421) embedded in the inner wall of the pipe column (22), and an upper magnetic conductive ring (422) and a lower magnetic conductive ring (423) arranged on the upper and lower end surfaces of the annular magnet (421); the upper magnetic conductive ring (422) and the lower magnetic conductive ring (423) are arranged radially corresponding to the upper side plate (411b) and the lower side plate (411c), respectively.

7. The implantable magnetic suspension blood pump according to claim 3, characterized in that: The top of the guide portion (121) protrudes into the inner cavity of the impeller body (21) and the top is less than or equal to 1 / 2 of the inner cavity of the impeller body (21). The top of the guide portion (121) is in the shape of a smooth conical surface. The gap between the tube column (22) and the groove (122) constitutes a secondary flow channel (C). After passing through the secondary flow channel (C), the blood is guided by the guide portion (121) to the inner cavity of the impeller body (21) and mixed with the blood in the inner cavity of the impeller body (21).

8. The implantable magnetic suspension blood pump according to claim 3, characterized in that: The motor stator assembly (31) is arranged in a space surrounded by the outer periphery of the groove (122), the inner wall of the middle shell (12) and the inner wall of the bottom shell (11), and includes a plurality of stator cores (311) arranged at intervals along the circumferential direction, the stator cores (311) including a vertical plate (311a), a top plate (311b) being arranged on the top of the vertical plate (311a), the stator coil (312) being wound around the outer periphery of the vertical plate (311a), the top plate (311b) being embedded in the middle shell (12) and forming a fixed connection, and a stator core (311b) being arranged between every two adjacent top plates (311b). A position sensor (315) is arranged, the position sensor is fixed on a position sensor PCB (316), the rotor magnet array (32) is arranged correspondingly to the stator core (311) on the radial circumference, an annular stator yoke (313) is arranged at the bottom of the stator core (311), the stator yoke (313) fixes the plurality of stator cores (311) into an integrated structure, a main control PCB (314) is also arranged in the inner cavity of the annular stator yoke (313), and the main control PCB (314) is fixed on the positioning column (123).

9. The implantable magnetic suspension blood pump according to claim 1, characterized in that: A first auxiliary annular magnet (23) is also provided in the upper plate surface of the impeller body (21); the first auxiliary annular magnet (23) and the end surface of a second auxiliary annular magnet (16) provided in the upper shell (13) are arranged opposite to each other, and the two are magnetically attracted to each other, thereby assisting the impeller (20) to maintain a centered state.

10. The implantable magnetic suspension blood pump according to claim 8, characterized in that: The bottom of the bottom shell (11) is provided with a plurality of support columns (17) protruding upwards, the tops of the support columns (17) abut against the stator iron core (311) and the magnetic suspension iron core (411) to form a limiting fit, and the bottom of the bottom shell (11) is also provided with a positioning groove (18), and the lower end of the positioning column (123) is inserted into the positioning groove (18) to form a limiting fit.

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