Blood pump

Abstract

The utility model relates to a blood pump. The blood pump comprises a pump shell, an impeller and a motor. The pump shell is provided with a fluid cavity and a first fixed magnet fixed in the fluid cavity. The impeller is rotatably arranged in the fluid cavity and provided with a first end and a second end which are opposite, the first end is provided with a center magnet, the second end is provided with a first movable magnet, the first fixed magnet is arranged around the center magnet, and a height difference exists between the first fixed magnet and the center magnet in the axial direction of the impeller, so that first magnetic force exists between the first fixed magnet and the center magnet. The motor and the second end of the impeller are oppositely arranged in the axial direction of the impeller. The motor comprises a shell and a stator arranged in the shell, the shell is fixedly connected with the pump shell, second magnetic force exists between the stator and the first movable magnet, and the first magnetic force can be matched with the second magnetic force to enable the impeller to suspend in the fluid cavity, namely, the impeller does not need to be driven by the rotating shaft to rotate, and a bearing does not need to be arranged. Therefore, bearing abrasion caused by friction between the rotating shaft and the bearing is avoided, and the service life of the blood pump is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a blood pump. Background Art

[0002] A blood pump is a medical device that uses biomechanical means to partially or completely replace the heart's blood pumping function to maintain blood circulation throughout the body. In a traditional blood pump, the impeller is assembled in the pump housing through the cooperation of the shaft and the bearing. The impeller rotates at high speed when in use, which may cause the bearing to wear faster and shorten the service life of the blood pump. Utility Model Content

[0003] Based on this, it is necessary to provide a blood pump, wherein the impeller of the blood pump is suspended in the fluid cavity, so that the wear of the impeller during rotation is greatly reduced, thereby extending the service life of the blood pump.

[0004] The present application proposes a blood pump, comprising:

[0005] A pump housing, wherein the pump housing is provided with a fluid cavity and a first fixed magnet fixed in the fluid cavity;

[0006] An impeller, the impeller being rotatably disposed in the fluid cavity, the impeller having a first end and a second end opposite to each other, the first end being provided with a central magnet, and the second end being provided with a first moving magnet; the first fixed magnet being disposed around the central magnet and having a height difference with the central magnet along the axial direction of the impeller, so that a first magnetic force exists between the first fixed magnet and the central magnet; and

[0007] A motor, wherein the motor and the second end of the impeller are arranged opposite to each other along the axial direction of the impeller; the motor comprises a housing and a stator arranged in the housing, the housing is fixedly connected to the pump casing, a second magnetic force exists between the stator and the first moving magnet, and the first magnetic force can cooperate with the second magnetic force to make the impeller suspended in the fluid cavity.

[0008] In one embodiment, the pump casing includes a mounting member fixed in the fluid chamber, the mounting member is provided with a center hole and a liquid flow hole located at the periphery of the center hole; wherein the first end of the impeller passes through the center hole; the first fixed magnet is mounted on the mounting member and surrounds the periphery of the center hole.

[0009] In one embodiment, the mounting member includes an annular portion and a plurality of mounting rods; wherein the annular portion has the center hole; the two ends of the mounting rod are respectively connected to the annular portion and the inner wall of the fluid chamber, the number of the liquid flow holes is multiple, and one liquid flow hole is formed between two adjacent mounting rods, and the first fixed magnet includes a plurality of magnetic blocks, each of which is arranged in one of the mounting rods.

[0010] In one embodiment, the second magnetic force is an attractive force, the upper surface of the first fixed magnet is higher than the upper surface of the central magnet, and the magnetic poles of the upper surface of the first fixed magnet are the same as the magnetic poles of the upper surface of the central magnet; or,

[0011] An upper surface of the first fixed magnet is lower than an upper surface of the central magnet, and a magnetic pole of the upper surface of the first fixed magnet is opposite to a magnetic pole of the upper surface of the central magnet.

[0012] In one embodiment, the stator includes an iron core and a coil wound around the iron core, and there is a first force F1 between the iron core and the first moving magnet. When the coil is energized, it can generate a second force F2 between the coil and the first moving magnet, wherein the directions of the first force F1 and the second force F2 are opposite, and the resultant force of the first force F1 and the second force F2 is the second magnetic force.

[0013] In one embodiment, the blood pump also includes a second moving magnet and a second fixed magnet, the second moving magnet is arranged on the side of the impeller close to the stator, the second fixed magnet is arranged in the outer casing and corresponds to the second moving magnet, there is a third magnetic force between the second moving magnet and the second fixed magnet, and the direction of the first magnetic force, the direction of the third magnetic force and the direction of the force between the coil and the first moving magnet after power is applied are the same.

[0014] In one embodiment, the stator includes a plurality of drive parts arranged along the circumference of the impeller, the plurality of drive parts are arranged around the second fixed magnet, and the first moving magnet is arranged around the second moving magnet; and / or the outer casing includes a distal cover, the distal cover is opposite to and spaced from the second end of the impeller along the axial direction of the impeller, and the second fixed magnet is embedded in the side of the distal cover away from the impeller.

[0015] In one embodiment, the impeller includes a main body and a base plate, the main body is provided with a groove capable of accommodating the first moving magnet, the base plate covers the groove to shield the first moving magnet, and the outer peripheral surface of the first moving magnet contacts the inner peripheral surface of the groove.

[0016] In one of the embodiments, the impeller includes a hub and blades arranged on the hub; two ends of the hub form the first end and the second end respectively, a cavity is provided inside the first end, and the central magnet is embedded in the cavity.

[0017] In one embodiment, the blood pump further comprises a sleeve assembly, wherein the sleeve assembly is connected to an end of the pump housing away from the motor, a first opening is provided at the end of the sleeve assembly away from the pump housing, and a second opening is provided at an end of the pump housing adjacent to the motor; one of the first opening and the second opening is a blood inlet; the other is a blood outlet.

[0018] In the technical solution of the present application, the blood pump includes a pump housing, an impeller and a motor. The pump housing is provided with a fluid cavity and a first fixed magnet fixed in the fluid cavity. The impeller is rotatably arranged in the fluid cavity. The first end and the second end of the impeller are respectively provided with a central magnet and a first moving magnet, wherein the first fixed magnet is arranged around the central magnet and has a height difference with the central magnet along the axial direction of the impeller to generate a first magnetic force. The motor and the second end of the impeller are arranged opposite to each other along the axial direction of the impeller, the outer shell of the motor is fixedly connected to the pump housing, and a second magnetic force exists between the stator arranged in the outer shell and the first moving magnet. Under the cooperation of the first magnetic force and the second magnetic force, the impeller is suspended in the fluid cavity, that is, the impeller does not need to be driven to rotate by the rotating shaft, and no bearing is required, thereby avoiding the situation where the bearing wear is caused by the friction between the rotating shaft and the bearing, and prolonging the service life of the blood pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG1 is a schematic diagram of the structure of the blood pump proposed in this application.

[0020] FIG. 2 is a schematic diagram of a partial structure of the blood pump shown in FIG. 1 .

[0021] FIG. 3 is an exploded view of the blood pump shown in FIG. 2 from a viewing angle.

[0022] FIG. 4 is an exploded view of the blood pump shown in FIG. 2 from another viewing angle.

[0023] FIG. 5 is a side view of the blood pump shown in FIG. 2 .

[0024] FIG. 6 is a cross-sectional view of FIG. 5 along the AA direction.

[0025] FIG. 7 is a partial exploded view of the impeller shown in FIG. 3 .

[0026] Description of Figure Numbers:

[0027] 100. Blood pump; 1. Pump housing; 11. Fluid chamber; 2. Impeller; 21. Main body; 212. Groove; 22. Bottom plate; 23. First end; 231. Cavity; 24. Second end; 25. Hub; 26. Blade; 3. First moving magnet; 4. Motor; 41. Housing; 411. Distal cover; 42. Stator; 421. Drive unit; 4211. Core; 4212. Coil; 5. Center magnet; 6. First fixed magnet; 61. Magnetic block; 7. Second fixed magnet; 8. Second moving magnet; 9. Mounting member; 90. Ring portion; 91. Liquid flow hole; 92. Mounting rod; 93. Center hole; 10. Sleeve assembly; 12. First opening; 13. Second opening. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0029] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0030] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated 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, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0032] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0033] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0034] A blood pump is a medical device that uses biomechanical means to partially or completely replace the heart's pumping function and maintain blood circulation throughout the body. Among them, interventional blood pumps are mostly used in high-risk percutaneous coronary interventions to reduce ventricular work and provide necessary circulatory support for cardiac recovery and early assessment of residual myocardial function. In traditional interventional blood pumps, the impeller rotates at high speed during use, which may cause the bearings to wear faster and affect the life of the blood pump.

[0035] In view of this, the present application proposes a blood pump, which aims to solve the problem in traditional invasive blood pumps that the high-speed rotation of the impeller causes the bearings to wear faster, thus affecting the life of the blood pump.

[0036] Referring to FIGS. 1 to 4 , the blood pump 100 proposed in the present application includes a pump housing 1, an impeller 2 and a motor 4. The pump housing 1 is provided with a fluid cavity 11 and a first fixed magnet 6 fixed in the fluid cavity 11. The impeller 2 is rotatably arranged in the fluid cavity 11, and has a first end 23 and a second end 24 opposite to each other. The first end 23 is provided with a central magnet 5, and the second end 24 is provided with a first moving magnet 3, wherein the first fixed magnet 6 is arranged around the central magnet 5, and has a height difference with the central magnet 5 along the axial direction of the impeller 2, so that there is a first magnetic force between the first fixed magnet 6 and the central magnet 5. The motor 4 is arranged opposite to the second end 24 of the impeller 2 along the axial direction of the impeller 2; the motor 4 includes a housing 41 and a stator 42 arranged in the housing 41, the housing 41 is fixedly connected to the pump housing 1, and there is a second magnetic force between the stator 42 and the first moving magnet 3, and the first magnetic force can cooperate with the second magnetic force to make the impeller 2 suspend in the fluid cavity 11.

[0037] The axial direction of the impeller 2 is the direction from the first end 23 to the second end 24 , and the radial direction of the impeller 2 is the direction perpendicular to the axial direction.

[0038] The impeller 2 includes a hub 25 and blades 26 arranged on the hub 25, and the two ends of the hub 25 respectively form a first end 23 and a second end 24, wherein a cavity 231 is provided inside the first end 23, and the central magnet 5 is embedded in the cavity 231 to avoid the central magnet 5 being arranged outside the first end 23 and avoiding direct contact between the central magnet 5 and the blood, so as to protect the blood.

[0039] Please continue to refer to FIG. 1 . The blood pump 100 further includes a sleeve assembly 10. The sleeve assembly 10 is connected to the end of the pump housing 1 away from the motor 4. The end of the sleeve assembly 10 away from the pump housing 1 is provided with a first opening 12, and the end of the pump housing 1 adjacent to the motor 4 is provided with a second opening 13. One of the first opening 12 and the second opening 13 is a blood inlet; the other is a blood outlet. The impeller 2 rotates in the fluid chamber 11, so that blood can enter the blood pump 100 from the blood inlet and flow out to the aorta or the pulmonary artery through the blood outlet to achieve the blood pumping function of the blood pump 100. In this embodiment, when the blood pump 100 is used for the left ventricle, the sleeve assembly 10 can be inserted into the aortic valve, so that the first opening 12 is the blood inlet and the second opening 13 is the blood outlet. In other embodiments, when the blood pump 100 is used for the right ventricle, the sleeve assembly 10 can be inserted into the pulmonary valve, so that the first opening 12 is the blood outlet and the second opening 13 is the blood inlet.

[0040] In the technical solution of the present application, the central magnet 5 and the first fixed magnet 6 generate a first magnetic force, the first moving magnet 3 and the stator 42 generate a second magnetic force, and both the first magnetic force and the second magnetic force are applied to the impeller 2, wherein the first moving magnet 3 is a Halbach array magnet, so that while the first moving magnet 3 and the stator 42 generate the second magnetic force, a rotating magnetic field can also be generated between the first moving magnet 3 and the stator 42 to drive the impeller 2 to rotate. The impeller 2 can be suspended in the fluid cavity 11 by the second magnetic force and the first magnetic force, so that the wear of the impeller 2 during rotation is greatly reduced, thereby extending the service life of the blood pump 100. Specifically, the impeller 2 does not need to be driven to rotate by the rotating shaft, and there is no need to set a bearing, thereby avoiding the situation where the friction between the rotating shaft and the bearing causes the bearing to wear. The first magnetic force and the second magnetic force should be of the same magnitude and opposite direction in theory, so that the impeller 2 can remain stable in the fluid cavity 11. Specifically, the first moving magnet 3 and the central magnet 5 are arranged on the impeller 2, and the stator 42 is arranged in the housing 41 of the motor 4 and corresponds to the first moving magnet 3. The first fixed magnet 6 is arranged in the fluid cavity 11 and surrounds the central magnet 5.

[0041] 2 and 6 , in some embodiments, the pump housing 1 includes a mounting member 9, which is fixed in the fluid cavity 11. Specifically, the mounting member 9 is connected to the cavity wall of the fluid cavity 11. The mounting member 9 can be used to mount the first fixed magnet 6.

[0042] The mounting member 9 is provided with a center hole 93 and a liquid flow hole 91 located on the periphery of the center hole 93, and the liquid flow hole 91 and the center hole 93 are both connected to the fluid cavity 11, wherein the center hole 93 can be used for the first end 23 of the impeller 2 to pass through, thereby limiting the radial deflection amplitude of the impeller 2 to a certain extent and improving the stability of the operation of the impeller 2. Since the central magnet 5 is embedded in the cavity 231, it is ensured that there is a sufficient gap between the impeller 2 and the hole wall of the center hole 93, thereby reducing the probability of the impeller 2 contacting the hole wall of the center hole 93 and improving the stability of the operation of the impeller 2. The liquid flow hole 91 can be used for the liquid entering from the blood inlet to flow into the fluid cavity 11. The center hole 93 can also allow liquid to flow into the fluid cavity 11.

[0043] The blood pump 100 needs to pump blood for the whole body of the patient during actual use, so the pump housing 1 is provided with a liquid flow hole 91. One end of the mounting member 9 is connected to the inner wall of the fluid cavity 11, and the first fixed magnet 6 is arranged on the mounting member 9 and surrounds the outer periphery of the central hole 93, so that the first fixed magnet 6 can be installed more stably in the fluid cavity 11. In this embodiment, the mounting member 9 can be arranged in a strip shape, and in other embodiments, the mounting member 9 can also be arranged in a columnar shape or other shapes.

[0044] In some embodiments, please refer to FIG. 2 again. The mounting member 9 includes an annular portion 90 and a plurality of mounting rods 92, wherein the annular portion 90 has a central hole 93; the two ends of the mounting rod 92 respectively connect the annular portion 90 and the inner wall of the fluid chamber 11, and the plurality of mounting rods 92 are arranged at intervals along the circumference of the impeller 2. There are a plurality of liquid flow holes 91, and a liquid flow hole 91 is formed between two adjacent mounting rods 92. The first fixed magnet 6 includes a plurality of magnetic blocks 61, and each magnetic block 61 is arranged in a mounting rod 92. In this way, on the one hand, the plurality of magnetic blocks 61 of the first fixed magnet 6 do not occupy the liquid flow hole 91, thereby ensuring the flow rate of the blood pump 100; on the other hand, the magnetic block 61 is arranged in the mounting rod 92, which can also prevent the magnetic block 61 from directly contacting the blood to protect the blood. In this application, a plurality refers to 6. In other embodiments, a plurality can also refer to other numbers of 3 or more.

[0045] The magnetic properties of the multiple magnetic blocks 61 are the same, and there is a height difference between each magnetic block 61 and the central magnet 5, so that the magnetic forces between the multiple magnetic blocks 61 and the central magnet 5 can jointly form a first magnetic force. In this embodiment, the multiple magnetic blocks 61 are aligned in the axial direction of the impeller 2. In other embodiments, the multiple magnetic blocks 61 can also have a height difference in the axial direction of the impeller 2, as long as the purpose of the magnetic forces between the multiple magnetic blocks 61 and the central magnet 5 can jointly form a first magnetic force.

[0046] In one embodiment of the present application, the second magnetic force is an attractive force. Along the axial direction of the impeller 2, the upper surface of the first fixed magnet 6 is higher than the upper surface of the central magnet 5, that is, the upper surface of the first fixed magnet 6 is farther away from the stator 42 relative to the upper surface of the central magnet 5, and the magnetic poles of the upper surface of the first fixed magnet 6 are the same as the magnetic poles of the upper surface of the central magnet 5, so that the first fixed magnet 6 and the central magnet 5 can attract the impeller 2 through the first magnetic force, that is, the first magnetic force between the first fixed magnet 6 and the central magnet 5 is an attractive force. Specifically, the impeller 2 will move away from the stator 42 under the action of the first magnetic force. In fact, the second magnetic force between the stator 42 and the first moving magnet 3 will cause the impeller 2 to move toward the stator 42, so the first magnetic force and the second magnetic force cooperate with each other to enable the impeller 2 to suspend in the fluid cavity 11.

[0047] In another embodiment of the present application, the upper surface of the first fixed magnet 6 is lower than the upper surface of the central magnet 5, that is, the upper surface of the first fixed magnet 6 is closer to the stator 42 than the upper surface of the central magnet 5, and the magnetic poles of the upper surface of the first fixed magnet 6 are opposite to the magnetic poles of the upper surface of the central magnet 5, so that the first magnetic force between the first fixed magnet 6 and the central magnet 5 is also an attractive force. The second magnetic force is also an attractive force, so the first magnetic force and the second magnetic force cooperate with each other to also enable the impeller 2 to suspend in the fluid chamber 11.

[0048] Please refer to FIG. 3 to FIG. 6. In some embodiments, the stator 42 includes an iron core 4211 and a coil 4212 wound around the iron core 4211. There is a first force F1 between the iron core 4211 and the first moving magnet 3. After the coil 4212 is energized, it can generate a second force F2 with the first moving magnet 3, wherein the first force F1 and the second force F2 are in opposite directions, and the resultant force of the first force F1 and the second force F2 is the second magnetic force. Since the second force F2 is generated between the coil 4212 and the first moving magnet 3 after being energized, the resultant force of the first force F1 and the second force F2 is the second magnetic force, and therefore, the second magnetic force is variable, so the magnitude of the second magnetic force can be controlled by adjusting the current or voltage of the energized coil 4212, thereby controlling the suspension height of the impeller 2.

[0049] In some embodiments, the blood pump 100 further includes a second fixed magnet 7 and a second moving magnet 8, the second fixed magnet 7 is disposed in the housing 41, the second moving magnet 8 is disposed on the side of the impeller 2 close to the stator 42, and corresponds to the second fixed magnet 7, a third magnetic force exists between the second moving magnet 8 and the second fixed magnet 7, and the direction of the first magnetic force, the direction of the third magnetic force, and the direction of the force (i.e., the second force F2) between the coil 4212 and the first moving magnet 3 after power-on are the same. In this way, by providing the second fixed magnet 7 and the second moving magnet 8, the force between the coil 4212 and the first moving magnet 3 after power-on can be reduced, thereby reducing the current or voltage flowing through the coil 4212, thereby saving energy. The first force F1 and the first magnetic force between the iron core 4211 and the first moving magnet 3 are relatively stable magnetic forces, and after the coil 4212 is energized, a second force F2 is generated between the energized coil 4212 and the first moving magnet 3. In specific applications, after the second fixed magnet 7 and the second moving magnet 8 are installed, the direction and magnitude of the second force F2 are adjusted by adjusting the direction and magnitude of the current in the coil 4212, so that the third magnetic force and the second force F2 can cooperate with each other to balance the first magnetic force and the second magnetic force, so that the impeller 2 is suspended in the fluid chamber 11.

[0050] In this embodiment, the second moving magnet 8 is an ordinary annular magnet, so that the direction of the force between the second fixed magnet 7 and the second moving magnet 8 is the axial direction of the impeller 2, and no torque is generated between the second fixed magnet 7 and the second moving magnet 8, so that the impeller 2 only rotates under the action of the torque between the first moving magnet 3 and the stator 42, thereby ensuring the stable rotation of the impeller 2.

[0051] In this embodiment, the direction of the third magnetic force is the same as the direction of the second force F2, so that the second fixed magnet 7 and the second moving magnet 8 can help the coil 4212 relieve the magnetic pressure, so that the current in the coil 4212 can be smaller, thereby saving energy. In other embodiments, when the first force F1 between the iron core 4211 and the first moving magnet 3 is small, the direction of the third magnetic force and the direction of the second force F2 can also be different, and adaptive adjustments can be made according to actual conditions.

[0052] In some embodiments, the stator 42 includes a plurality of driving parts 421 arranged along the circumference of the impeller 2 , the plurality of driving parts 421 are arranged around the second fixed magnet 7 , and the first moving magnet 3 is arranged around the second moving magnet 8 .

[0053] Specifically, each driving unit 421 includes an iron core 4211 and a coil 4212 wound around the iron core 4211 .

[0054] The plurality of driving parts 421 are arranged around the second fixed magnet 7, so that the second fixed magnet 7 can make full use of the internal space surrounded by the plurality of driving parts 421, so that the stator 42 and the second fixed magnet 7 are installed more closely, and the space occupied is smaller, which is conducive to the miniaturization of the blood pump 100. Similarly, the first moving magnet 3 is arranged around the second moving magnet 8, and the installation of the first moving magnet 3 and the second moving magnet 8 will also be more closely, and the utilization rate of the internal space of the blood pump 100 will also be higher, which is conducive to the miniaturization of the blood pump 100.

[0055] When the distance between the second fixed magnet 7 and the second moving magnet 8 is relatively small, the third magnetic force between the second fixed magnet 7 and the second moving magnet 8 will be relatively larger, which is beneficial to reduce the current or voltage required to flow through the coil 4212, thereby reducing the power consumption of the blood pump 100 when in use. Therefore, in some embodiments of the present application, the housing 41 includes a distal cover 411, the distal cover 411 and the second end 24 of the impeller 2 are opposite and spaced along the axial direction of the impeller 2, and the second fixed magnet 7 is embedded in the side of the distal cover 411 away from the impeller 2. For example, the side of the distal cover 411 away from the impeller 2 is provided with a mounting groove, and the mounting groove can be installed with the second fixed magnet 7, so that the distance between the second fixed magnet 7 and the second moving magnet 8 is closer, the third magnetic force between the second moving magnet 8 and the second fixed magnet 7 is increased, and the current or voltage required by the coil 4212 is further reduced, which can save energy.

[0056] In actual use, the impeller 2 will rotate at a high speed, which will subject the impeller 2 and other structures mounted on the impeller 2 to a certain centrifugal force. Therefore, in some embodiments, the impeller 2 includes a main body 21 and a bottom plate 22 (as shown in FIG. 7 ), the main body 21 is provided with a groove 212 capable of accommodating the first moving magnet 3, the bottom plate 22 is covered in the groove 212 to shield the first moving magnet 3, and the outer peripheral surface of the first moving magnet 3 is in contact with the inner peripheral surface of the groove 212.

[0057] The impeller 2 is provided with a groove 212 to install the first moving magnet 3, and the groove 212 can limit the radial movement of the first moving magnet 3 in the impeller 2 through its own side wall, thereby avoiding the first moving magnet 3 from being offset due to the influence of centrifugal force, ensuring the stability of the second magnetic force between the stator 42 and the first moving magnet 3, so that the impeller 2 can rotate stably in the fluid chamber 11.

[0058] In summary, the blood pump 100 provided in the present application includes a pump housing 1, an impeller 2 and a motor 4, wherein the pump housing 1 is provided with a fluid cavity 11 and a first fixed magnet 6 fixed in the fluid cavity 11, the impeller 2 is rotatably arranged in the fluid cavity 11, and the first end 23 and the second end 24 of the impeller 2 are respectively provided with a central magnet 5 and a first moving magnet 3, wherein the first fixed magnet 6 is arranged around the central magnet 5, and has a height difference with the central magnet 5 along the axial direction of the impeller to generate a first magnetic force. The motor 4 and the second end 24 of the impeller are arranged oppositely along the axial direction of the impeller 2, the housing 41 of the motor 4 is fixedly connected to the pump housing 1, and a second magnetic force is provided between the stator 42 arranged in the housing 41 and the first moving magnet 3. Under the cooperation of the first magnetic force and the second magnetic force, the impeller 2 is suspended in the fluid cavity 11, that is, the impeller 2 does not need to be driven to rotate by the rotating shaft, and no bearing is required, thereby avoiding the situation where the friction between the rotating shaft and the bearing causes the bearing to wear, and prolonging the service life of the blood pump 100.

[0059] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A blood pump, characterized in that: include: A pump housing, wherein the pump housing is provided with a fluid cavity and a first fixed magnet fixed in the fluid cavity; An impeller, the impeller being rotatably disposed in the fluid cavity, the impeller having a first end and a second end opposite to each other, the first end being provided with a central magnet, and the second end being provided with a first moving magnet; the first fixed magnet being disposed around the central magnet and having a height difference with the central magnet along the axial direction of the impeller, so that a first magnetic force exists between the first fixed magnet and the central magnet; and A motor, wherein the motor and the second end of the impeller are arranged opposite to each other along the axial direction of the impeller; the motor comprises a housing and a stator arranged in the housing, the housing is fixedly connected to the pump casing, a second magnetic force exists between the stator and the first moving magnet, and the first magnetic force can cooperate with the second magnetic force to make the impeller suspended in the fluid cavity.

2. The blood pump according to claim 1, characterized in that The pump casing includes a mounting member fixed in the fluid cavity, wherein the mounting member is provided with a center hole and a plurality of liquid flow holes located at the periphery of the center hole; wherein the first end of the impeller passes through the center hole; and the first fixed magnet is mounted on the mounting member and surrounds the periphery of the center hole.

3. The blood pump according to claim 2, characterized in that The mounting member includes an annular portion and a plurality of mounting rods; wherein the annular portion has the center hole; the two ends of the mounting rod are respectively connected to the annular portion and the inner wall of the fluid cavity, the number of the liquid flow holes is multiple, and one liquid flow hole is formed between two adjacent mounting rods; the first fixed magnet includes a plurality of magnetic blocks, and each of the magnetic blocks is arranged in one of the mounting rods.

4. The blood pump according to claim 1, characterized in that The second magnetic force is an attractive force, the upper surface of the first fixed magnet is higher than the upper surface of the central magnet, and the magnetic poles of the upper surface of the first fixed magnet are the same as the magnetic poles of the upper surface of the central magnet; or, An upper surface of the first fixed magnet is lower than an upper surface of the central magnet, and a magnetic pole of the upper surface of the first fixed magnet is opposite to a magnetic pole of the upper surface of the central magnet.

5. The blood pump according to claim 1, characterized in that The stator includes an iron core and a coil wound around the iron core, wherein a first force F1 is present between the iron core and the first moving magnet, and the coil can generate a second force F2 between the coil and the first moving magnet after being energized, wherein the directions of the first force F1 and the second force F2 are opposite, and the resultant force of the first force F1 and the second force F2 is the second magnetic force.

6. The blood pump according to claim 5, characterized in that The blood pump also includes a second moving magnet and a second fixed magnet. The second moving magnet is arranged on a side of the impeller close to the stator. The second fixed magnet is arranged in the outer casing and corresponds to the second moving magnet. There is a third magnetic force between the second moving magnet and the second fixed magnet. The direction of the first magnetic force, the direction of the third magnetic force, and the direction of the force between the coil and the first moving magnet after power is applied are the same.

7. The blood pump according to claim 6, characterized in that The stator includes a plurality of driving parts arranged along the circumference of the impeller, the plurality of driving parts are arranged around the second fixed magnet, and the first moving magnet is arranged around the second moving magnet; and / or the outer casing includes a distal cover, the distal cover is opposite to and spaced from the second end of the impeller along the axial direction of the impeller, and the second fixed magnet is embedded in a side of the distal cover away from the impeller.

8. The blood pump according to any one of claims 1 to 7, characterized in that: The impeller includes a main body and a bottom plate, the main body is provided with a groove capable of accommodating the first moving magnet, the bottom plate is covered in the groove to shield the first moving magnet, and the outer circumference of the first moving magnet contacts the inner circumference of the groove.

9. The blood pump according to any one of claims 1 to 7, characterized in that: The impeller includes a hub and blades arranged on the hub; two ends of the hub form the first end and the second end respectively, a cavity is arranged inside the first end, and the central magnet is embedded in the cavity.

10. The blood pump according to claim 1, characterized in that The blood pump also includes a sleeve assembly, which is connected to the end of the pump housing away from the motor. The end of the sleeve assembly away from the pump housing is provided with a first opening, and the end of the pump housing adjacent to the motor is provided with a second opening; one of the first opening and the second opening is a blood inlet; the other is a blood outlet.

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