Artificial heart magnetic suspension axial flow shaftless blood pump

Abstract

The invention discloses a magnetic suspension axial flow shaftless blood pump for an artificial heart. The magnetic suspension axial flow shaftless blood pump comprises a pump shell, a stator assembly arranged in the pump shell and a rotor assembly arranged in the stator assembly in a suspension mode. The rotor assembly comprises a rotor cylinder of a cylindrical structure and axial flow blades with one ends fixed to the inner wall of the rotor cylinder and the other ends extending towards the center, and an inner channel of the rotor cylinder forms a first blood flow channel. A second blood flow channel which surrounds the first blood flow channel and is coaxial with the first blood flow channel is formed between the stator assembly and the inner wall of the pump shell. A new solution is provided from the perspective of fluid dynamics, the hemolysis or thrombus risk can be effectively reduced, the damage to blood cells is reduced, and the use safety is improved.

Description

Technical Field

[0001] The invention belongs to the field of medical devices, and in particular relates to an artificial heart magnetically suspended axial flow shaftless blood pump. Background Art

[0002] Artificial heart magnetic levitation axial flow shaftless blood pump is an advanced device in the field of heart failure treatment. Its core goal is to mimic the function of the natural heart, while reducing complications such as thrombosis and hemolysis through contactless drive and optimized hemodynamic design. This type of blood pump relies on magnetic levitation technology to eliminate the friction and wear particle sources of traditional bearings. The axial flow design makes the blood flow path short and straight, reduces the volume, and is suitable for implantation in the body; its core components include: magnetic levitation rotor system, which applies magnetic field force in the radial direction of the rotor through permanent magnets or electromagnets to offset gravity or centrifugal force and achieve contactless suspension between the rotor and the stator; axial flow impeller, the impeller is usually directly integrated on the rotor, the blades are spiral or inclined, and axial blood flow is generated by rotation. The blade shape is optimized to reduce turbulence; stator and housing, the stator contains an excitation coil (electromagnetic drive type) or a permanent magnet (permanent magnet drive type), the housing is a biocompatible material such as titanium alloy, and is lined with ultra-smooth polymers (such as polyetheretherketone, PEEK) to reduce the blood contact area.

[0003] Existing magnetic levitation axial flow pump products include Medtronic's HeartMate 3, Boston Scientific's HVAD and Solingen Group's CorNeck. Similar patents include a new axial flow artificial heart pump disclosed in CN205322884U or an axial flow magnetic levitation blood pump with pulsating speed regulation characteristics disclosed in CN107441573B.

[0004] However, including the above examples, existing magnetic levitation axial flow blood pumps are all single-channel structures. Since there is only one flow path, it often leads to excessive pressure at the outlet, which increases the impact on the blood vessels and causes hemolysis or thrombosis. In addition, high-speed blood flow will produce high shear stress in narrow channels, damaging blood cells. Although these problems can be partially alleviated through material improvements (such as nano-coatings) and algorithm optimization (such as adaptive control), there are still certain limitations and the feasibility remains to be explored.

[0005] The above technical problems need to be solved. Summary of the invention

[0006] In order to overcome the above technical problems, the present invention proposes an artificial heart magnetically suspended axial flow shaftless blood pump, which provides a new solution from the perspective of fluid dynamics, reduces the risk of hemolysis or thrombosis, reduces damage to blood cells, and improves safety of use.

[0007] The technical solution adopted by the present invention to solve the technical problem is:

[0008] Provided is an artificial heart magnetically suspended axial flow shaftless blood pump, comprising a pump housing, a stator assembly arranged in the pump housing, and a rotor assembly suspended in the stator assembly; the rotor assembly comprises a rotor barrel with a cylindrical structure and an axial flow blade with one end fixed to the inner wall of the rotor barrel and the other end extending toward the center; the internal channel of the rotor barrel forms a first blood flow channel;

[0009] A second blood flow channel surrounding the first blood flow channel and coaxial with the first blood flow channel is formed between the stator assembly and the inner wall of the pump housing.

[0010] As a further improvement, the pump housing is of a cylindrical structure; the stator assembly includes a stator barrel of a cylindrical structure, and the stator barrel is connected to the pump housing via a connecting piece, so that a gap is formed between the stator barrel and the inner wall of the pump housing.

[0011] As a further improvement, there are multiple connecting members, and the multiple connecting members are evenly distributed on a circumference with the center of the pump housing as the center.

[0012] As a further improvement, the pump casing, stator barrel and rotor barrel are coaxially arranged.

[0013] As a further improvement, the rotor assembly further comprises a moving magnet disposed on the rotor barrel; the stator assembly further comprises a first fixed magnet and a second fixed magnet disposed on the stator barrel;

[0014] The first fixed magnet generates a repulsive force on the moving magnet, suspending the rotor barrel in the internal channel of the stator barrel; the second fixed magnet generates an eccentric magnetic force on the moving magnet, driving the rotor barrel to rotate in the internal channel of the stator barrel, driving the axial flow blades to rotate and generate axial thrust on the incoming blood.

[0015] As a further improvement, there are multiple moving magnets, and the multiple moving magnets are evenly spaced along the circumferential direction on the outer wall of the rotor tube to form a magnetically suspended rotating body.

[0016] As a further improvement, there are a plurality of the first magnets and the second magnets, and the first magnets and the second magnets are evenly and spacedly distributed on the inner wall of the stator barrel along the circumferential direction.

[0017] As a further improvement, the moving magnet and the first fixed magnet are permanent magnet structures, and the second fixed magnet is a coil winding structure.

[0018] As a further improvement, wire passages for arranging electrical wires are provided in the pump housing, the connecting piece and the stator barrel.

[0019] As a further improvement, a plurality of battery boxes are fixed to the inner wall of the pump housing, and batteries for powering the electronic components of the blood pump are installed in the battery boxes.

[0020] The beneficial effects of the present invention are:

[0021] An artificial heart magnetically suspended axial flow shaftless blood pump provided by the present invention creatively adds a second blood flow channel to form a dual-channel structure; the first blood flow channel serves as the main flow channel and is responsible for efficiently pushing blood, while the second blood flow channel forms an auxiliary circulation, which can balance the axial pressure distribution, reduce local pressure gradient mutations, and reduce impact and turbulence on the blood vessel wall. The second blood flow channel disperses blood flow energy and can also reduce shear stress in high-speed blood flow areas, thereby reducing the risks of red blood cell rupture and platelet activation.

[0022] The present invention provides a new solution from the perspective of fluid dynamics, which can effectively reduce the risk of hemolysis or thrombosis, reduce damage to blood cells, and improve safety of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of a first three-dimensional structure of the present invention;

[0024] Figure 2 It is a schematic diagram of a second three-dimensional structure of the present invention;

[0025] Figure 3 It is a schematic diagram of the main structure of the present invention.

[0026] In the figure: 1-pump housing; 2-rotor cylinder; 3-axial flow blades; 4-first blood flow channel; 5-second blood flow channel; 6-stator cylinder; 7-connecting piece; 8-moving magnet; 9-first fixed magnet; 10-second fixed magnet; 11-battery box. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with the accompanying drawings.

[0028] Example

[0029] like Figures 1 to 3 As shown: This embodiment specifically discloses an artificial heart magnetically suspended axial flow shaftless blood pump, including a pump housing 1, a stator assembly arranged in the pump housing 1, and a rotor assembly suspended in the stator assembly; the rotor assembly includes a rotor barrel 2 with a cylindrical structure and an axial flow blade 3 with one end fixed to the inner wall of the rotor barrel 2 and the other end extending toward the center; the internal channel of the rotor barrel 2 forms a first blood flow channel 4.

[0030] The pump housing 1 can be made of titanium alloy or medical grade polymer (such as PEEK) to ensure biocompatibility and mechanical strength; the magnetic suspension principle and axial flow pumping principle between the rotor assembly and the stator assembly can be the same as the prior art and will not be repeated here.

[0031] The artificial heart magnetically suspended axial flow shaftless blood pump of this embodiment is mainly special in that a second blood flow channel 5 surrounding the first blood flow channel 4 and coaxial with the first blood flow channel 4 is formed between the stator assembly and the inner wall of the pump housing 1 .

[0032] The first blood flow channel 4 is an axial flow path formed inside the rotor barrel 2, and the blood is directly pushed forward by the rotation of the axial flow blades 3; the second blood flow channel 5 is an annular gap between the stator assembly and the pump housing 1, and the blood flows along the gap (powered by the blood flow in the first blood flow channel 4 and the pressure difference), forming an auxiliary circulation path coaxial with the first blood flow channel 4.

[0033] The blood pump of this embodiment creatively adds a second blood flow channel 5 to form a dual-channel structure; the first blood flow channel 4 serves as the main flow channel and is responsible for efficiently pushing blood, while the second blood flow channel 5 forms an auxiliary circulation, which can balance the axial pressure distribution, reduce local pressure gradient mutations, and reduce the impact and turbulence on the blood vessel wall. The second blood flow channel 5 disperses blood flow energy and can also reduce the shear stress in the high-speed blood flow area, thereby reducing the risk of red blood cell rupture (hemolysis) and platelet activation.

[0034] In principle, the second blood flow channel 5 mainly achieves the reduction of pressure and shear stress through the triple mechanism of diverting kinetic energy, optimizing pressure distribution and suppressing turbulence; this structure not only meets the biocompatibility requirements of the blood pump, but also may improve energy efficiency (reduce driving power requirements), providing a new technical path for the research and development of the next generation of artificial hearts.

[0035] Specifically:

[0036] First, the second blood flow channel 5 is coaxially distributed around the main channel, and can absorb part of the kinetic energy at the outlet of the main channel by guiding part of the blood to flow through the gap of the side wall of the pump body (similar to a "ring bypass"), and convert it into static pressure energy, which is equivalent to forming a dynamic pressure release path in the pump body, thereby reducing the peak pressure at the outlet of the main channel;

[0037] Second, the second blood flow channel 5 can extend the gradient of the axial static pressure distribution through its flow path to reduce the local pressure mutation. For example, in the middle section of the pump, the auxiliary flow of the second blood flow channel 5 can offset the radial pressure deviation of the first blood flow channel 4 caused by the centrifugal force caused by the rotation of the impeller;

[0038] Third, the flow of the second blood flow channel 5 can absorb part of the kinetic energy of the first blood flow channel 4, and make the flow velocity distribution in the first blood flow channel 4 smoother through momentum transfer. For example, the flow of the second blood flow channel 5 can induce the formation of a secondary circulation (similar to a vortex ring in a cylindrical flow) in the first blood flow channel 4, destroying the boundary layer separation of the high-speed jet and reducing the axial velocity gradient.

[0039] Fourth, the annular flow of the second blood flow channel 5 can "constrain" the blood flow of the first blood flow channel 4, limiting the generation of turbulent vortices; experiments show that the turbulent kinetic energy in the annular flow channel is 30%-50% lower than that in the straight channel, thereby significantly reducing the shear stress;

[0040] Fifth, the second blood flow channel 5 can be used as an "elastic energy storage space" to absorb instantaneous flow changes when the pump output does not match the physiological demand (such as blood pressure fluctuations), reduce the pulsating flow intensity in the first blood flow channel 4, and further reduce the shear stress peak;

[0041] Sixth, the flow of the second blood flow channel 5 can utilize part of the energy of the rotation of the axial flow blades 3 in the first blood flow channel 4, and the auxiliary circulation can be maintained without additional energy consumption;

[0042] Seventh, the blood flowing in the second blood flow channel 5 can assist in cooling the magnetically suspended rotor and the stator, indirectly reducing the change in fluid viscosity caused by the temperature increase and maintaining the shear stress stable.

[0043] In this embodiment, the pump housing 1 is a cylindrical structure; the stator assembly includes a stator barrel 6 of a cylindrical structure, and the stator barrel 6 is connected to the pump housing 1 through a connector 7, so that a gap is formed between the stator barrel 6 and the inner wall of the pump housing 1, and this gap constitutes the second blood flow channel 5. The connector 7 can be a fixed connecting plate structure, which can adopt a thin-wall design or a streamlined structure to reduce interference with blood flow; the gap formed is a fixed gap; the surface of the connector 7 can be smoothed, and the smooth surface can reduce the risk of blood retention and thrombosis.

[0044] Preferably, the number of the connectors 7 is multiple (for example, three), and the multiple connectors 7 are evenly distributed on the circumference with the center of the pump housing 1 as the center, thereby improving the stability and symmetry of the structure. The pump housing 1 is a cylindrical structure, and the connectors 7 are evenly distributed on the circumference to ensure balanced force and avoid local stress concentration; this is very important for the stable operation of the magnetic suspension system, because any imbalance may cause the rotor to deviate, increasing the risk of wear or downtime.

[0045] In this embodiment, the pump housing 1, stator barrel 6 and rotor barrel 2 are coaxially arranged to further optimize the flow symmetry and stability of the magnetic levitation; the coaxial arrangement means that the central axes of the three components completely coincide, which can reduce radial deviation, which is very important for the magnetic levitation system because any deviation will cause friction or instability; secondly, in terms of hemodynamics, the coaxial structure helps to maintain laminar flow, reduce turbulence and shear stress, and is very helpful in reducing the risk of hemolysis.

[0046] In this embodiment, the rotor assembly also includes a dynamic magnet 8 arranged on the rotor barrel 2; the stator assembly also includes a first fixed magnet 9 and a second fixed magnet 10 arranged on the stator barrel 6; the first fixed magnet 9 generates a repulsive force on the dynamic magnet 8, suspending the rotor barrel 2 in the internal channel of the stator barrel 6; the second fixed magnet 10 generates an eccentric magnetic force on the dynamic magnet 8, driving the rotor barrel 2 to rotate in the internal channel of the stator barrel 6, driving the axial flow blades 3 to rotate and generate axial thrust on the incoming blood.

[0047] The magnets form a combined magnetic suspension and drive system that combines the stable suspension of permanent magnets and the precise control of electromagnets. Repulsive suspension reduces friction, while eccentric magnetic drive provides more efficient torque transmission. The combined design separates the magnetic suspension from the drive function, achieving contactless suspension and efficient rotational drive of the rotor assembly, providing a simpler and more reliable motion control solution for the artificial heart.

[0048] By adjusting the distribution of magnetic force, it is possible to achieve smoother rotation and lower shear stress, thereby reducing the risk of hemolysis and thrombosis; for example, in the present embodiment, the number of the moving magnets 8 is multiple (for example, twelve), and the multiple moving magnets 8 are evenly spaced along the circumferential direction on the outer wall of the rotor tube 2 to form a magnetically suspended rotating body; the number of the first magnet and the second magnet is multiple (for example, six), and the first magnet and the second magnet are evenly and spacedly distributed along the circumferential direction on the inner wall of the stator tube 6; the moving magnet 8 and the first fixed magnet 9 are permanent magnet structures, and the second fixed magnet 10 is a coil winding structure.

[0049] The moving magnet 8 is a plurality of permanent magnets uniformly distributed along the circumferential direction on the outer wall of the rotor tube 2, which is responsible for magnetic suspension; the first fixed magnet 9 is also a permanent magnet, which is also distributed on the inner wall of the stator tube 6, and interacts with the moving magnet 8 to generate repulsive force to achieve suspension; the second fixed magnet 10 is a coil winding structure, which can be used to generate magnetic force to drive the rotor; the combination of permanent magnets and coils realizes the functions of both suspension and driving, while maintaining a compact and efficient structure; suspension and drive are independently regulated, and the speed is infinitely adjustable by adjusting the current frequency and phase of the second fixed magnet 10.

[0050] In this embodiment, the pump housing 1, the connecting piece 7 and the stator tube 6 are provided with wire passage holes (not shown in the figure) for arranging electrical conductors; the main function of the wire passage holes is to provide power transmission for the electromagnetic drive system, such as powering the coil of the second fixed magnet 10; without affecting the structural integrity, this structure can effectively manage the layout of wires while ensuring the reliability and biocompatibility of the blood pump.

[0051] In this embodiment, a plurality of battery boxes 11 are fixed to the inner wall of the pump housing 1, and batteries (not shown in the figure) for powering the electronic components of the blood pump are installed in the battery boxes 11. The number of battery boxes 11 can also be multiple, and the multiple battery boxes 11 are evenly distributed on the circumference of a circle with the center of the pump housing 1 as the center; wireless power supply and extended battery life can be achieved through batteries.

[0052] Of course, the above description is not limited to the above examples. Technical features not described in the present invention can be achieved by or by using existing technologies, which will not be described here. The above embodiments and drawings are only used to illustrate the technical scheme of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not depart from the purpose of the present invention, and should also fall within the scope of protection of the claims of the present invention.

Claims

1. An artificial heart magnetically suspended axial flow shaftless blood pump, comprising a pump housing, a stator assembly disposed in the pump housing, and a rotor assembly suspended in the stator assembly; the rotor assembly comprises a rotor barrel with a cylindrical structure and an axial flow blade with one end fixed to the inner wall of the rotor barrel and the other end extending toward the center, the internal channel of the rotor barrel forming a first blood flow channel; characterized in that: A second blood flow channel surrounding the first blood flow channel and coaxial with the first blood flow channel is formed between the stator assembly and the inner wall of the pump housing.

2. The artificial heart magnetic suspension axial flow shaftless blood pump according to claim 1, characterized in that: The pump housing is of a cylindrical structure; the stator assembly comprises a stator barrel of a cylindrical structure, and the stator barrel is connected to the pump housing via a connecting piece, so that a gap is formed between the stator barrel and the inner wall of the pump housing.

3. The artificial heart magnetic suspension axial flow shaftless blood pump according to claim 2, characterized in that: There are multiple connecting parts, and the multiple connecting parts are evenly distributed on the circumference of a circle with the center of the pump housing as the center.

4. The artificial heart magnetic suspension axial flow shaftless blood pump according to claim 2, characterized in that: The pump casing, stator barrel and rotor barrel are coaxially arranged.

5. The artificial heart magnetic suspension axial flow shaftless blood pump according to claim 2, characterized in that: The rotor assembly further comprises a moving magnet disposed on the rotor barrel; the stator assembly further comprises a first fixed magnet and a second fixed magnet disposed on the stator barrel; The first fixed magnet generates a repulsive force on the moving magnet, so that the rotor barrel is suspended in the internal channel of the stator barrel; The second fixed magnet generates an eccentric magnetic force on the moving magnet, driving the rotor barrel to rotate in the internal channel of the stator barrel, driving the axial flow blades to rotate and generate an axial thrust on the incoming blood.

6. The artificial heart magnetic suspension axial flow shaftless blood pump according to claim 5, characterized in that: There are multiple moving magnets, and the multiple moving magnets are evenly spaced along the circumferential direction and arranged on the outer wall of the rotor tube to form a magnetic suspension rotating body.

7. The artificial heart magnetic suspension axial flow shaftless blood pump according to claim 6, characterized in that: There are a plurality of the first magnets and the second magnets, and the first magnets and the second magnets are evenly and spacedly distributed on the inner wall of the stator barrel along the circumferential direction.

8. The artificial heart magnetic suspension axial flow shaftless blood pump according to claim 6, characterized in that: The moving magnet and the first fixed magnet are permanent magnet structures, and the second fixed magnet is a coil winding structure.

9. An artificial heart magnetically suspended axial flow shaftless blood pump according to any one of claims 2 to 8, characterized in that: The pump housing, the connecting piece and the stator barrel are provided with wire passages for arranging electric wires.

10. An artificial heart magnetically suspended axial flow shaftless blood pump according to any one of claims 2 to 8, characterized in that: A plurality of battery boxes are fixed on the inner wall of the pump housing, and batteries for supplying power to the electronic components of the blood pump are installed in the battery boxes.

Images