Centrifugal magnetic levitation artificial heart pump

Abstract

The invention relates to the technical field of artificial heart pumps, and discloses a centrifugal magnetic suspension artificial heart pump. The centrifugal magnetic suspension artificial heart pump comprises: a centrifugal assembly, comprising a first housing and an impeller with a gap located in the first housing, the impeller being able to rotate around the Z axis relative to the first housing; a suspension rotation assembly, comprising a second housing and a magnetic suspension rotating motor arranged in the second housing, the magnetic suspension rotating motor comprising a rotor, a stator, a suspension winding, a driving winding, a permanent magnet ring and a magnetic cover plate, the stator gap ring being arranged on the outer periphery of the rotor, the upper and lower ends of the rotor being covered with magnetic cover plates, the upper and lower end surfaces of the stator being arranged with permanent magnet rings, the gap of the magnetic cover plate being located on the inner side of the permanent magnet ring, the stator being wound with a suspension winding and a driving winding, the driving winding being energized to drive the rotor to rotate around the Z axis at a balanced position, and the impeller being coaxial with the rotor and drivingly connected. The centrifugal magnetic suspension artificial heart pump can stably suspend and rotate the rotor at a balanced position.

Description

Technical Field

[0001] The invention relates to the technical field of artificial heart pumps, in particular to a centrifugal magnetic suspension artificial heart pump. Background Art

[0002] At present, using artificial heart pumps to replace heart function has become the key to prolonging the lives of patients with heart disease. Among them, the most important parts of the artificial heart pump are the impeller used to pump blood and the suspension motor that provides power for the impeller. Whether the structure of the impeller is optimized greatly affects the magnitude of the shear force exerted on the blood during pumping, that is, the degree of damage to the blood cells. The suspension performance of the suspension motor directly affects the suspension of the impeller, and thus affects the stability of the impeller pumping blood.

[0003] Since the suspension of the rotor in the current suspension motor is poor, the suspension of the impeller connected to the rotor drive is also poor, causing the impeller to shift or deflect during rotation, and then causing the impeller to touch the outer casing located outside the impeller, resulting in poor stability in the impeller pumping blood.

[0004] Therefore, there is an urgent need for a centrifugal magnetically levitated artificial heart pump that can solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a centrifugal magnetic levitation artificial heart pump, which can make the rotor stably suspend and rotate at a balanced position to ensure the stability of the impeller pumping blood.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] Centrifugal magnetic levitation artificial heart pump, comprising:

[0008] A centrifugal assembly, comprising a first housing and an impeller with a gap in the first housing, wherein the impeller is rotatable relative to the first housing about a Z axis so that the impeller can generate a centrifugal force on the blood entering the first housing;

[0009] A suspension rotating assembly, comprising a second housing and a magnetic suspension rotating motor arranged in the second housing, wherein the second housing is located at the bottom end of the first housing, and the magnetic suspension rotating motor comprises a rotor, a stator, a suspension winding, a driving winding, a permanent magnet ring and a magnetic cover plate, wherein the stator gap ring is arranged on the outer periphery of the rotor, the upper and lower ends of the rotor are both covered with the magnetic cover plates, the upper and lower end surfaces of the stator are both provided with the permanent magnet ring, the magnetic cover plate gap is located on the inner side of the permanent magnet ring, the suspension winding and the driving winding are wound around the stator, the driving winding is energized to drive the rotor to rotate around the Z axis at a balanced position, the impeller is coaxial with the rotor and is drivingly connected, and the Z axis is parallel to the axial direction of the rotor;

[0010] Among them, the suspension winding is energized to generate a suspension magnetic field with the same direction as the magnetic field of the permanent magnet ring, so as to generate a radial suspension force, thereby pulling the rotor that is offset in the direction opposite to the radial suspension force back to the equilibrium position; a magnetic flux loop can be formed between the stator, the rotor, and the permanent magnet ring and the magnetic cover plate located on the same side, and the magnetic resistance theorem closes the magnetic flux loop along the minimum path of the magnetic lines of force, so as to pull the rotor that has generated axial movement and axial deflection back to the equilibrium position, and the path of the magnetic flux loop is the smallest when the rotor is at the equilibrium position.

[0011] Furthermore, the shaft diameter ratio of the rotor is less than or equal to 1:3.

[0012] Furthermore, the permanent magnet ring comprises:

[0013] A first permanent magnet ring and a second permanent magnet ring are stacked on each other, wherein the magnetizing direction of the first permanent magnet ring is axially outward of the rotor, and the magnetizing direction of the second permanent magnet ring is radially inward of the rotor, the first permanent magnet ring and the second permanent magnet ring can form a Halbach array, and the magnetizing directions of the two first permanent magnet rings placed on the upper and lower end surfaces of the stator are in opposite directions in the axial direction of the rotor.

[0014] Furthermore, the thickness of the first permanent magnet ring is 1.8 to 2 times the thickness of the second permanent magnet ring.

[0015] Furthermore, the first permanent magnet ring and the second permanent magnet ring are both made of neodymium iron boron.

[0016] Furthermore, the suspension offset of the rotor in the radial direction is ±0.2 mm, and the suspension offset of the rotor in the axial direction is ±0.5 mm.

[0017] Furthermore, the centrifugal magnetic levitation artificial heart pump also includes:

[0018] A detection component is arranged in the second housing, and the detection component includes two eddy current displacement sensors and multiple Hall sensors. The two eddy current displacement sensors are respectively used to detect the offset of the rotor on the X-axis and the Y-axis in the radial direction, and the Hall sensor is used to detect the rotation speed of the rotor. The eddy current displacement sensor is connected to the suspension winding signal.

[0019] Furthermore, a PCB board is also arranged in the second housing, and the PCB board is connected to the eddy current displacement sensor and the Hall sensor signal.

[0020] Furthermore, the detection component also includes:

[0021] A sensor shaft, one end of which can pass through the inner hole of the rotor, and the sensor shaft is provided with two mounting holes with an angle of 90°, and the two mounting holes are respectively used to mount two eddy current displacement sensors.

[0022] Furthermore, the impeller is designed by CFturbo software and obtained by Fluent flow field simulation, and the outer diameter of the impeller is 25mm-26mm, the width of the impeller blades on the Z axis is 4.70mm-4.75mm, and the number of the blades is 6-7.

[0023] The beneficial effects of the present invention are:

[0024] The present invention proposes a centrifugal magnetic suspension artificial heart pump, which makes the stator gap ring of the magnetic suspension rotating motor be arranged on the outer periphery of the rotor, and the driving winding is wound on the stator, and the driving winding is energized to drive the rotor to rotate around the Z axis at the equilibrium position, and the impeller and the rotor are coaxial and drivingly connected, so that the rotor can drive the impeller to rotate around the Z axis relative to the first shell, so that the impeller can generate centrifugal force on the blood entering the inner side of the first shell, and the purpose of the impeller pumping blood is achieved; at the same time, magnetic cover plates are covered on the upper and lower ends of the rotor, and on the stator Permanent magnet rings are arranged on both the upper and lower end surfaces, so that the gap of the magnetic cover plate is located on the inner side of the permanent magnet ring, and a suspension winding is also wound on the stator; when the suspension winding is energized, it can generate a suspension magnetic field in the same direction as the magnetic field of the permanent magnet ring, so that the air gap magnetic density in the same direction also gradually increases, thereby generating a radial suspension force in the same direction. The generated radial suspension force can pull the rotor that is offset in the direction opposite to the radial suspension force back to the equilibrium position, so as to ensure the active suspension of the rotor in the radial direction and prevent radial offset; at the same time, the stator The stator, the rotor, and the permanent magnet ring and the magnetic cover plate located on the same side can form a magnetic flux loop with each other, and according to the magnetic resistance theorem, it can be known that the magnetic lines of force are always closed along the magnetic flux loop with the minimum path, and the path of the magnetic flux loop when the rotor is in the equilibrium position is the smallest. Therefore, when the rotor produces axial movement and axial deflection and deviates from the equilibrium position, the rotor can be subjected to an axial suspension force opposite to the deviation direction to pull the rotor back to the equilibrium position; in the present invention, a suspension winding is wound on the stator to achieve active suspension of the rotor in the radial direction; a magnetic flux loop is formed between the stator, the rotor, and the permanent magnet ring and the magnetic cover plate located on the same side, and according to the magnetic resistance theorem, passive suspension of the rotor in the axial direction can be achieved, so that the rotor can always be stably suspended and rotated at the equilibrium position, so that the impeller coaxially connected to the rotor can be stably suspended in the first housing and rotated, and the impeller will not be offset or deflected during the rotation process, causing the impeller to touch the first housing located outside the impeller, thereby ensuring the stability of the impeller pumping blood. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The structure of the centrifugal magnetic suspension artificial heart pump provided by the present invention is shown in FIG. Figure 1 ;

[0026] Figure 2 The structure of the centrifugal magnetic suspension artificial heart pump (excluding the pump housing) provided by the present invention is shown in FIG. Figure 2 ;

[0027] Figure 3 The structure diagram of the centrifugal magnetic suspension artificial heart pump provided by the present invention (excluding the first shell and the second shell) is shown in FIG. Figure 3 ;

[0028] Figure 4 is a cross-sectional view of a centrifugal magnetic suspension artificial heart pump provided by the present invention;

[0029] Figure 5 It is a structural schematic diagram of the magnetic levitation rotating motor (excluding two packaging plates) provided by the present invention;

[0030] Figure 6 The present invention provides Figure 5 Schematic diagram of the reverse structure in ;

[0031] Figure 7 It is a schematic diagram of the rotor magnetic suspension provided by the present invention;

[0032] Figure 8 It is a schematic diagram of the rotor axial passive suspension provided by the present invention;

[0033] Fig. 9 It is a schematic diagram of the principle of the rotor radial active suspension provided by the present invention.

[0034] Reference numerals:

[0035] 1-centrifugal assembly; 11-first housing; 111-pump housing; 1111-blood inlet; 1112-blood outlet; 112-lower sealing plate; 12-impeller; 121-blade; 122-guide cone;

[0036] 2-suspended rotating assembly; 21-second housing; 211-casing; 212-rear cover; 22-magnetic levitation rotating motor; 221-rotor; 222-stator; 2221-iron core; 2222-iron ring; 223-suspended winding; 224-driving winding; 225-permanent magnet ring; 2251-first permanent magnet ring; 2252-second permanent magnet ring; 226-magnetic cover; 227-magnetic flux loop; 2281-Hall sensor; 2282-sensor shaft; 2283-eddy current displacement sensor; 229-PCB board; 220-packaging board;

[0037] 3-Package screws. DETAILED DESCRIPTION

[0038] In order to make the technical problem solved by the present invention, the technical solution adopted and the technical effect achieved more clearly, the technical solution of the present invention is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0039] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0041] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the structure or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0042] At present, due to the poor suspension of the rotor in the suspension motor of the artificial heart pump, the suspension of the impeller of the artificial heart pump connected to the rotor drive is also poor, causing the impeller to offset or deflect during rotation, and then causing the impeller to touch the outer casing located on the outside of the impeller, resulting in poor stability in pumping blood by the impeller.

[0043] In this regard, this embodiment proposes a centrifugal magnetic levitation artificial heart pump that can achieve the function of pumping blood and has good suspension performance, thereby ensuring the stability of the blood during centrifugal pumping. Specifically, Figure 1-Figure 9As shown, the centrifugal magnetic suspension artificial heart pump includes a centrifugal component 1 and a suspension rotating component 2; wherein the centrifugal component 1 includes a first housing 11 and an impeller 12 with a gap located in the first housing 11, and the impeller 12 can rotate around the Z axis relative to the first housing 11, so that the impeller 12 can generate centrifugal force on the blood entering the inner side of the first housing 11, thereby realizing centrifugal blood pumping; the suspension rotating component 2 includes a second housing 21 and a magnetic suspension rotating motor 22 arranged inside the second housing 21, and the second housing 21 is located at the bottom end of the first housing 11; and the magnetic suspension rotating motor 22 includes a rotor 221, a stator 222 and a rotor 221. The stator 222, the suspension winding 223, the driving winding 224, the permanent magnet ring 225 and the magnetic cover plate 226, the stator 222 gap ring is arranged on the outer periphery of the rotor 221, the upper and lower ends of the rotor 221 are covered with magnetic cover plates 226, the upper and lower end surfaces of the stator 222 are provided with permanent magnet rings 225, the gap of the magnetic cover plate 226 is located on the inner side of the permanent magnet ring 225, the suspension winding 223 and the driving winding 224 are wound on the stator 222, the driving winding 224 is energized to drive the rotor 221 to rotate around the Z axis at the equilibrium position, and the impeller 12 is coaxial with the rotor 221 and is drivingly connected. Among them, the Z axis is parallel to the axial direction of the rotor 221, and the Z axis is specifically as follows: Figure 5 As shown by the arrow Z in FIG. 1 . The axial direction and radial direction involved in this embodiment refer to the axial direction of the rotor 221 and the radial direction of the rotor 221. In this embodiment, the equilibrium position of the rotor 221 specifically refers to the position where the rotor 221 is vertical and the gap is set inside the stator 222.

[0044] Specifically, energizing the suspension winding 223 can generate a suspension magnetic field with the same direction as the magnetic field of the permanent magnet ring 225, so as to generate a radial suspension force, thereby pulling the rotor 221 that is offset in the direction opposite to the radial suspension force back to the equilibrium position; a magnetic flux loop 227 can be formed between the stator 222, the rotor 221, and the permanent magnet ring 225 and the magnetic cover plate 226 located on the same side, and the magnetic resistance theorem causes the magnetic flux loop 227 with the minimum path of the magnetic lines of force to be closed, so as to pull the rotor 221 that has produced axial movement and axial deflection back to the equilibrium position, and the path of the magnetic flux loop 227 is the smallest when the rotor 221 is at the equilibrium position.

[0045] By making the stator 222 of the magnetic levitation rotating motor 22 gap-ring-arranged on the outer periphery of the rotor 221, and winding the driving winding 224 on the stator 222, energizing the driving winding 224 can drive the rotor 221 to rotate around the Z axis at the equilibrium position, and make the impeller 12 coaxial with the rotor 221 and drive connected, even if the impeller 12 is located directly above the rotor 221, and one end of the impeller 12 is interference-inserted into the inner hole of the rotor 221, so that the rotation of the rotor 221 can drive the impeller 12 to rotate synchronously around the Z axis relative to the first housing 11, so that the impeller 12 can generate centrifugal force on the blood entering the inner side of the first housing 11, thereby achieving the purpose of the impeller 12 pumping blood. The stator 222 includes an iron ring 2222 and a plurality of iron cores 2221 . The plurality of iron cores 2221 are evenly arranged on the inner side of the iron ring 2222 . A gap is set between the iron cores 2221 and the rotor 221 . The suspension winding 223 and the driving winding 224 are wound on the iron cores 2221 .

[0046] At the same time, magnetic cover plates 226 are provided at both upper and lower ends of the rotor 221, and permanent magnet rings 225 are provided at both upper and lower end surfaces of the iron core 2221 of the stator 222 close to the rotor 221, so that the gap of the magnetic cover plate 226 is located inside the permanent magnet ring 225, and a suspension winding 223 is also wound on the stator 222; when the suspension winding 223 is energized, a suspension magnetic field with the same magnetic field direction as the permanent magnet ring 225 can be generated, so that the air gap magnetic density in the same direction is gradually increased, thereby generating a magnetic field in the same direction. The radial suspension force generated can pull the rotor 221 that is offset in the direction opposite to the radial suspension force back to the equilibrium position to ensure the active suspension of the rotor 221 in the radial direction without radial offset; at the same time, the stator 222, the rotor 221, and the permanent magnet ring 225 and the magnetic cover plate 226 located on the same side can form a magnetic flux loop 227 with each other, and according to the magnetic resistance theorem, it can be known that the magnetic lines of force are always closed along the magnetic flux loop 227 of the minimum path, and the magnetic flux when the rotor 221 is in the equilibrium position The path of the loop 227 is the smallest. Therefore, when the rotor 221 moves axially and deflects axially and deviates from the equilibrium position, the rotor 221 is subjected to an axial suspension force opposite to the deviation direction to pull the rotor 221 back to the equilibrium position. In the present invention, the suspension winding 223 is wound on the stator 222 to realize active suspension in the radial direction of the rotor 221. The magnetic flux loop 227 is formed between the stator 222, the rotor 221, and the permanent magnet ring 225 and the magnetic cover plate 226 on the same side, and according to the magnetic resistance Theorem can realize the passive suspension of the rotor 221 in the axial direction, so that the rotor 221 can always be stably suspended and rotated at the equilibrium position, so that the impeller 12 coaxially driven and connected to the rotor 221 can be stably suspended in the first shell 11 and rotate, and there will be no problem that the impeller 12 will be offset or deflected during the rotation and cause the impeller 12 to touch the first shell 11 located outside the impeller 12, thereby ensuring the stability of the impeller 12 in pumping blood and avoiding adverse effects such as thrombosis and hemolysis on the blood.

[0047] Specifically, the suspension winding 223 and the drive winding 224 can be powered on and work independently of each other, the suspension winding 223 can generate a suspension magnetic field, and the drive winding 224 can generate a drive magnetic field; and the suspension winding 223 and the drive winding 224 are arranged at intervals on the stator 222 to reduce mutual interference between the drive magnetic field and the suspension magnetic field.

[0048] Furthermore, the shaft diameter ratio of the rotor 221 is less than or equal to 1:3, so that the axial length of the rotor 221 is much smaller than the radial length of the rotor 221, so that the minimum magnetic resistance position of the rotor 221 is relatively concentrated, and the magnetic resistance force on the rotor 221 is large enough to maintain the passive suspension of the rotor 221 during axial displacement and axial deflection, which helps to improve the stability of the axial suspension of the rotor 221. In this embodiment, the shaft diameter ratio of the rotor 221 is equal to 1:3.

[0049] Specifically, if Figure 1-Figure 6 As shown, the permanent magnet ring 225 includes a first permanent magnet ring 2251 and a second permanent magnet ring 2252 stacked on each other; wherein, the magnetization direction of the first permanent magnet ring 2251 is axially outward of the rotor 221, and the magnetization direction of the second permanent magnet ring 2252 is radially inward of the rotor 221; the first permanent magnet ring 2251 and the second permanent magnet ring 2252 can form a Halbach array with each other, and the Halbach array can generate the strongest magnetic field with the least number of permanent magnet rings; and the magnetization directions of the two first permanent magnet rings 2251 placed on the upper and lower end surfaces of the iron core 2221 of the stator 222 are in opposite directions in the axial direction of the rotor 221. The Halbach array in this embodiment is a common magnet structure, so the specific principle of the Halbach array will not be described in detail here.

[0050] By placing the first permanent magnet ring 2251 in the permanent magnet ring 225 on the stator 222, on the one hand, the electromagnetic performance of the magnetic levitation rotating motor 22 can be improved, and on the other hand, the problem of reduced blood compatibility caused by direct contact of the permanent magnet ring 225 with blood in the prior art can be avoided, thereby improving blood compatibility and reducing the human body's rejection reaction to the centrifugal magnetic levitation artificial heart pump.

[0051] Further, the thickness of the first permanent magnet ring 2251 is 1.8 to 2 times the thickness of the second permanent magnet ring 2252, so as to ensure the magnetic properties of the Halbach array formed by the first permanent magnet ring 2251 and the second permanent magnet ring 2252. In this embodiment, the thickness of the first permanent magnet ring 2251 is twice the thickness of the second permanent magnet ring 2252. In this embodiment, the first permanent magnet ring 2251 and the second permanent magnet ring 2252 are both made of neodymium iron boron, which has good magnetic properties, thereby improving the rotation performance, radial suspension and axial suspension performance of the rotor 221.

[0052] Specifically, Figure 5-Figure 9As shown, for the upper half of the rotor 221, the magnetic lines of force on the stator 222 pass through the first permanent magnet ring 2251 and the second permanent magnet ring 2252, both located above, and then pass through the air gap between the second permanent magnet ring 2252 and the magnetic cover plate 226 to the magnetic cover plate 226 located on the upper end surface of the rotor 221, and then pass through the rotor 221, and finally from the rotor 221 to the air gap between the rotor 221 and the stator 222, and then return to the stator 222, and finally generate air gap magnetic density with the same polarity in the air gap between the rotor 221 and the stator 222, so that a magnetic flux loop 227 can be formed between the stator 222, the rotor 221, and the permanent magnet ring 225 and the magnetic cover plate 226 located on the same side; the magnetic flux loop 227 formed in the lower half of the rotor 221 is similar to that in the upper half of the rotor 221, that is, the rotor 221 The magnetic flux circuit 227 formed in the lower half is specifically, stator 222—the first permanent magnet ring 2251 and the second permanent magnet ring located on the lower end surface of the stator 222—the air gap between the second permanent magnet ring 2252 and the magnetic cover plate 226 on the lower end surface of the rotor 221—the magnetic cover plate 226 on the lower end surface of the rotor 221—the rotor 221—the air gap between the rotor 221 and the stator 222—the stator 222; at the same time, according to the magnetic resistance theorem, it can be known that the magnetic lines of force are always closed along the magnetic flux circuit 227 with the minimum path, and the path of the magnetic flux circuit 227 when the rotor 221 is in the equilibrium position is the smallest. Therefore, when the rotor 221 produces axial movement and axial deflection and deviates from the equilibrium position, the rotor 221 can be subjected to an axial suspension force opposite to the deviation direction to pull the rotor 221 back to the equilibrium position, thereby realizing axial passive suspension of the rotor 221.

[0053] Furthermore, if Figure 5-Figure 7 and Fig. 9 As shown, the principle of generating the radial suspension force of the rotor 221 is the magnetic pulling force in the radial direction generated by the combined action of two magnetic fields with different pole pairs; the specific principle is as follows Fig. 9 As shown, when current is passed through the suspension winding 223, the direction of the suspension magnetic field generated by the suspension winding 223 is the same as the direction of the magnetic field generated by the permanent magnet ring 225 on the X+ axis, and the air gap magnetic density on the X+ axis also gradually increases, while on the X- axis it is the opposite; therefore, a radial suspension force in the X+ direction can be generated, and the radial suspension force can pull the rotor 221 that is offset to the X- axis back to the equilibrium position; wherein, Fig. 9 The X+ axis and the X-axis refer to two opposite directions in the radial direction of the rotor 221, and the X-axis is specifically the radial offset direction of the rotor 221. Correspondingly, the principle of the rotor 221 generating radial suspension force on the Y+ axis is similar to that on the X+ axis, and will not be described in detail here.

[0054] When the rotor 221 is radially offset to any position due to external disturbance, the offset position of the rotor 221 can be decomposed into the offset in the X-axis direction and the offset in the Y-axis direction, so that the radial suspension force in the X+ axis direction and the radial suspension force in the Y+ axis direction can be generated respectively, and finally the stable suspension of the rotor 221 in the radial direction is achieved. Among them, the angle between the X-axis and the Y-axis is 90° and is located in the same horizontal plane as the radial direction of the rotor 221, and the X-axis and the Y-axis refer to the offset directions of the rotor 221 on the X-axis and the Y-axis respectively. Among them, Figure 5 The arrow X and arrow Y in the figure merely indicate the directions of the X-axis and the Y-axis by way of example, but the directions of the X-axis and the Y-axis are not limited thereto, as long as the two mutually perpendicular directions in the radial direction of the rotor 221 can form the X-axis and the Y-axis respectively.

[0055] Through the above process, it can be understood that Figure 7 As shown, the rotor 221 is passively controlled in the axial suspension direction by the magnetic flux circuit 227, while the rotor 221 is actively controlled in the radial suspension direction according to the radial offset of the rotor 221 on the X-axis and the Y-axis.

[0056] By passively suspending the rotor 221 in the axial direction and actively suspending it in the radial direction, it is possible to ensure that, in addition to enabling the rotor 221 to rotate around the Z axis, the rotor 221 is fully magnetically suspended in five degrees of freedom, so that the rotor 221 can be stably suspended in a balanced position and rotate. The suspension of the rotor 221 in the five degrees of freedom specifically refers to three degrees of freedom: axial offset in the axial direction, axial leftward deflection, and axial rightward deflection, and two degrees of freedom: radial offset in the X-axis and Y-axis in the radial direction. By suspending the rotor 221 in the axial direction and in the radial direction, it is possible to ensure that the suspension offset of the rotor 221 in the radial direction relative to the equilibrium position is ±0.2 mm, and the suspension offset of the rotor 221 in the axial direction relative to the equilibrium position is ±0.5 mm, thereby ensuring the stable suspension of the impeller 12 in the first housing 11.

[0057] Furthermore, the centrifugal magnetic suspension artificial heart pump further comprises a detection component, which is arranged in the second housing 21. Figure 4-Figure 6As shown, the detection component includes two eddy current displacement sensors 2283 and multiple Hall sensors 2281. The two eddy current displacement sensors 2283 are respectively used to detect the radial offset of the rotor 221 on the X-axis and the Y-axis. The Hall sensor 2281 is used to detect the rotation speed of the rotor 221. The eddy current displacement sensor 2283 is connected to the suspension winding 223 signal, so that the current passed through the suspension winding 223 can be controlled according to the detection values ​​of the two eddy current displacement sensors 2283, thereby ensuring that the generated radial suspension force can accurately pull the rotor 221 back to the equilibrium position; that is, a closed-loop control can be formed between the current passed through the suspension winding 223 and the radial offset displacement of the rotor 221 on the X-axis and the Y-axis detected by the eddy current displacement sensor 2283, thereby ensuring the radial suspension of the rotor 221. In this embodiment, there are four Hall sensors 2281 , which are disposed between two adjacent cores 2221 of the stator 222 , and the distance between two adjacent Hall sensors 2281 is 90°, so that the rotation speed of the rotor 221 can be detected more accurately.

[0058] Specifically, if Figure 2-Figure 4 and Figure 6 As shown, the magnetic suspension rotating motor 22 further includes two packaging plates 220, which are respectively located at the upper and lower ends of the stator 222, so as to package the rotor 221, the stator 222 and the permanent magnet ring 225 in the second housing 21; and a printed circuit board (PCB) is also provided in the second housing 21. The PCB board 229 is arranged between the stator 222 and the lower packaging board 220. The PCB board 229 is connected to the eddy current displacement sensor 2283 and the Hall sensor 2281 by signal, so that the detection signals of the eddy current displacement sensor 2283 and the Hall sensor 2281 can be transmitted to the master controller through the PCB board 229, so that the master controller can control the magnitude of the current of the suspension winding 223 according to the detection signal of the eddy current displacement sensor 2283, and at the same time, the master controller can control the magnitude of the current of the driving winding 224 according to the detection signal of the Hall sensor 2281; and other sensors and inlet and outlet wires in the magnetic suspension rotating motor 22 can also be integrated and arranged on the PCB board 229, so as to facilitate the unified arrangement of sensors and wires, and greatly reduce the errors of wire wiring and assembly. The master controller in this embodiment is a common controller structure in the prior art, and the control principle of the master controller is not described in detail here.

[0059] Specifically, Figure 4-Figure 6As shown, the detection component also includes a sensor shaft 2282, one end of which can pass through the inner hole of the rotor 221, and two mounting holes with an angle of 90° are provided on the sensor shaft 2282, and the two mounting holes are respectively used to install two eddy current displacement sensors 2283, so that the eddy current displacement sensor 2283 can detect the radial offset of the rotor 221.

[0060] Furthermore, if Figure 1-Figure 4 As shown, the first housing 11 includes a pump housing 111 and a lower sealing plate 112. A blood inlet 1111 and a blood outlet 1112 are arranged on the pump housing 111. The blood inlet 1111 extends along the axial direction of the rotor 221. The blood outlet 1112 is tangent to the outer peripheral surface of the pump housing 111. The pump housing 111 and the lower sealing plate 112 form a pump chamber, and the impeller 12 is arranged at the center of the pump chamber. When the centrifugal magnetic suspension artificial heart pump is working, blood enters the pump chamber from the blood inlet 1111 through the medical catheter, and is guided to the blades 121 of the impeller 12 through the tip of the guide cone 122 on the top of the impeller 12, so that the centrifugal force generated under the high-speed rotation of the impeller 12 can make the blood in the pump chamber have a certain fluid kinetic energy, and the blood is transmitted to the blood outlet 1112 to flow out. Wherein, the pump housing 111 is made of a transparent material so that the working condition of the impeller 12 can be observed from outside the pump housing 111.

[0061] Specifically, the impeller 12 is obtained through CFturbo software design and Fluent flow field simulation optimization, so that all parameters of the impeller 12 are relatively optimized. For example, the outer diameter of the impeller 12 is 25mm-26mm, the width of the blades 121 of the impeller 12 on the Z axis is 4.70mm-4.75mm, and the number of blades 121 is 6-7, so that the shear force on the blood is small when pumping blood, and the degree of damage to the blood cells is small, so that the impeller 12 can minimize the damage to the blood when pumping blood at high speed. The CFturbo software design and Fluent flow field simulation in this embodiment are both common technical means in the prior art, and the specific analysis and simulation process will not be described in detail here.

[0062] Furthermore, if Figure 1-Figure 4As shown, the second shell 21 includes a rear cover plate 212 and a casing 211, the lower sealing plate 112 is arranged on the top end surface of the casing 211, the rear cover plate 212 is fixedly covered on the bottom end surface of the casing 211 by means of packaging screws 3, one end of the sensor shaft 2282 is fixed on the rear cover plate 212 by bolts, and the other end of the sensor shaft 2282 can extend into the inner hole of the rotor 221; and the lower sealing plate 112, the casing 211 and the rear cover plate 212 can surround and form a closed space, and the magnetic levitation rotating motor 22 is arranged at the center of the closed space; wherein, the pump casing 111, the lower sealing plate 112 and the casing 211 are packaged into an integral structure by means of packaging screws 3, so that the centrifugal component 1 and the suspended rotating component 2 can be assembled into an integral structure, thereby making the structure of the entire centrifugal magnetic levitation artificial heart pump relatively simple, the layout compact, and the disassembly and assembly are relatively simple and convenient, and it is easy to be implanted in the human body.

[0063] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A centrifugal magnetic levitation artificial heart pump, characterized in that: include: A centrifugal assembly (1), comprising a first housing (11) and an impeller (12) with a gap located in the first housing (11), wherein the impeller (12) is capable of rotating around a Z axis relative to the first housing (11), so that the impeller (12) can generate a centrifugal force on blood entering the first housing (11); A suspension rotating assembly (2) comprises a second housing (21) and a magnetic suspension rotating motor (22) arranged in the second housing (21), wherein the second housing (21) is located at the bottom end of the first housing (11), the magnetic suspension rotating motor (22) comprises a rotor (221), a stator (222), a suspension winding (223), a drive winding (224), a permanent magnet ring (225) and a magnetic cover plate (226), wherein a gap ring of the stator (222) is arranged on the outer periphery of the rotor (221), the upper and lower ends of the rotor (221) are both covered with the magnetic cover plates (226), and the stator (222) is provided with a magnetic cover plate (226). The permanent magnet ring (225) is disposed on both upper and lower end surfaces of the iron core (2221) of the stator (222) on a side close to the rotor (221); the magnetic cover plate (226) is located at the inner side of the permanent magnet ring (225); the suspension winding (223) and the driving winding (224) are wound on the stator (222); the driving winding (224) is energized to drive the rotor (221) to rotate around the Z axis at a balanced position; the impeller (12) is coaxial with the rotor (221) and is drivingly connected; the Z axis is parallel to the axial direction of the rotor (221); Wherein, the suspension winding (223) is energized to generate a suspension magnetic field having the same direction as the magnetic field of the permanent magnet ring (225), so as to generate a radial suspension force, thereby pulling the rotor (221) that is offset in a direction opposite to the direction of the radial suspension force back to the equilibrium position; A magnetic flux loop (227) can be formed between the stator (222), the rotor (221), the permanent magnet ring (225) and the magnetic cover plate (226) located on the same side, and the magnetic resistance theorem closes the magnetic flux loop (227) along the minimum path of the magnetic lines of force, so as to pull the rotor (221) that has axial movement and axial deflection back to the equilibrium position. When the rotor (221) is at the equilibrium position, the path of the magnetic flux loop (227) is the minimum.

2. The centrifugal magnetic levitation artificial heart pump according to claim 1, characterized in that: The shaft diameter ratio of the rotor (221) is less than or equal to 1:

3.

3. The centrifugal magnetic levitation artificial heart pump according to claim 1, characterized in that: The permanent magnet ring (225) comprises: A first permanent magnet ring (2251) and a second permanent magnet ring (2252) are stacked on each other, wherein the magnetization direction of the first permanent magnet ring (2251) is axially outward of the rotor (221), and the magnetization direction of the second permanent magnet ring (2252) is radially inward of the rotor (221), the first permanent magnet ring (2251) and the second permanent magnet ring (2252) can form a Halbach array, and the magnetization directions of the two first permanent magnet rings (2251) placed on the upper and lower end surfaces of the stator (222) are in opposite directions in the axial direction of the rotor (221).

4. The centrifugal magnetic levitation artificial heart pump according to claim 3, characterized in that: The thickness of the first permanent magnet ring (2251) is 1.8 to 2 times the thickness of the second permanent magnet ring (2252).

5. The centrifugal magnetic levitation artificial heart pump according to claim 3, characterized in that: The first permanent magnet ring (2251) and the second permanent magnet ring (2251) are both made of neodymium iron boron.

6. The centrifugal magnetic levitation artificial heart pump according to any one of claims 1 to 5, characterized in that: The suspension offset of the rotor (221) in the radial direction is ±0.2 mm, and the suspension offset of the rotor (221) in the axial direction is ±0.5 mm.

7. The centrifugal magnetic levitation artificial heart pump according to any one of claims 1 to 5, characterized in that: The centrifugal magnetic levitation artificial heart pump also includes: A detection component is arranged in the second housing (21), the detection component comprising two eddy current displacement sensors (2283) and a plurality of Hall sensors (2281), the two eddy current displacement sensors (2283) being used to detect the offset of the rotor (221) on the X-axis and the Y-axis in the radial direction respectively, the Hall sensor (2281) being used to detect the rotation speed of the rotor (221), and the eddy current displacement sensor (2283) being connected to the suspension winding (223) by signal.

8. The centrifugal magnetic levitation artificial heart pump according to claim 7, characterized in that: A PCB board (229) is also provided in the second housing (21), and the PCB board (229) is signal-connected to the eddy current displacement sensor (2283) and the Hall sensor (2281).

9. The centrifugal magnetic levitation artificial heart pump according to claim 7, characterized in that: The detection component also includes: A sensor shaft (2282), one end of which can pass through the inner hole of the rotor (221), and the sensor shaft (2282) is provided with two mounting holes with an angle of 90°, and the two mounting holes are respectively used to mount the two eddy current displacement sensors (2283).

10. The centrifugal magnetic levitation artificial heart pump according to any one of claims 1 to 5, characterized in that: The impeller (12) is designed by CFturbo software and obtained by Fluent flow field simulation, and the outer diameter of the impeller (12) is 25 mm-26 mm, the width of the blades (121) of the impeller (12) on the Z axis is 4.70 mm-4.75 mm, and the number of the blades (121) is 6-7.

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