A magnetic levitation pump with symmetrical hollow thin-wall configuration and control method thereof

Abstract

The present invention discloses a magnetic levitation pump with a symmetrical hollow thin-wall configuration and a control method thereof. The magnetic levitation pump with a symmetrical hollow thin-wall configuration comprises a shell, magnetic levitation blades and a magnetic levitation drive assembly. The shell comprises an upper pump shell and a lower pump shell sealed with the upper pump shell. The magnetic levitation blades are arranged in the shell and have symmetrical cavities. The magnetic levitation blades are located between the cavities and have a hollow liquid inlet channel. The positions located outside the cavities form a thin-wall channel connected to the hollow liquid inlet channel with the inner wall of the lower pump shell. The magnetic levitation drive assembly is used to control and drive the magnetic levitation blades to rotate in the shell. The present invention optimizes the flow channel design of the pump and uses a microcontroller to control radial and axial stator currents in real time to achieve high-speed rotation and suspension of the rotor blades, which can greatly suppress turbulence when blood flows through, reduce eddy currents and local high shear areas, improve fluid dynamics characteristics, and reduce hemolysis.

Description

Technical Field

[0001] The invention relates to the technical field of biomedicine, in particular to a magnetic suspension pump with a symmetrical hollow thin-wall configuration and a control method thereof. Background Art

[0002] Ventricular Assist Device (VAD) plays a vital role in the treatment of heart disease. The hemolytic performance of VAD devices is a key factor that must be taken into account during their design and use. Hemolysis, that is, the rupture of red blood cells to release hemoglobin, not only causes anemia, but may also cause renal failure and other complications. Therefore, reducing the hemolysis rate is crucial to improving the safety and effectiveness of VAD devices.

[0003] Traditional mechanical axial flow pumps are prone to high shear forces and blood turbulence during operation due to the mechanical bearings and contact parts in their design. These high shear forces and turbulence are one of the main causes of hemolysis. During the blood pumping process of the mechanical axial flow pump, blood cells deform and rupture under high shear forces, resulting in hemolysis. In addition, wear and loss of mechanical contact parts also increase the risk of hemolysis.

[0004] In contrast, the magnetic levitation centrifugal pump uses non-contact magnetic levitation technology, eliminating the presence of mechanical bearings and greatly reducing mechanical friction and contact wear. However, despite the significant advantage of magnetic levitation centrifugal pumps in reducing mechanical wear, they still produce a certain degree of turbulence and high shear force when rotating at high speeds, leading to hemolysis problems. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] Therefore, the purpose of the present invention is to provide a magnetic levitation pump with a symmetrical hollow thin-wall configuration and a control method thereof, which can effectively reduce blood turbulence and shear force by optimizing the design of the flow channel structure and combining advanced state-space intelligent control technology, thereby significantly reducing hemolysis and improving the safety and effectiveness of VAD equipment.

[0007] To solve the above technical problems, according to one aspect of the present invention, the present invention provides the following technical solutions:

[0008] A magnetic levitation pump with a symmetrical hollow thin-wall configuration, comprising:

[0009] A housing, comprising an upper pump housing and a lower pump housing sealed to the upper pump housing;

[0010] The magnetic suspension blade is arranged in the housing and has symmetrical cavities, and the position of the magnetic suspension blade between the cavities has a liquid inlet hollow channel, and the position outside the cavity forms a thin-walled channel connected to the liquid inlet hollow channel with the inner wall of the lower pump housing;

[0011] The magnetic suspension drive assembly is used to control and drive the magnetic suspension blade to rotate in the shell.

[0012] As a preferred solution of the magnetic levitation pump with a symmetrical hollow thin-wall configuration described in the present invention, barb rings are equidistantly arranged on the outer wall of the liquid inlet pipe of the upper pump housing.

[0013] As a preferred solution of the symmetrical hollow thin-walled magnetic levitation pump described in the present invention, the outer wall of the lower pump shell is provided with a liquid outlet pipe, and the interior thereof is provided with an annular liquid outlet channel connected with the thin-wall channel.

[0014] As a preferred solution of a symmetrical hollow thin-walled magnetic levitation pump described in the present invention, the magnetic levitation blades are surrounded by the upper pump shell and the lower pump shell to form a first slow flow cavity connected to the liquid inlet hollow channel, and a symmetrical second slow flow cavity is opened on the inner wall of the magnetic levitation blades at positions on both sides of the liquid inlet hollow channel.

[0015] As a preferred solution of a symmetrical hollow thin-walled magnetic levitation pump described in the present invention, the magnetic levitation drive assembly includes a ring seat coaxially arranged with the housing, a radial stator magnetic levitation module arranged on the side wall of the ring seat and arranged equidistantly, an axial stator magnetic levitation module embedded in the bottom of the ring seat, a radial rotor magnetic levitation module arranged on the inner wall of the cavity and arranged equidistantly, an axial rotor magnetic levitation module arranged at the bottom of the cavity, and a microcontroller;

[0016] The microcontroller collects the voltages of the radial rotor magnetic suspension module and the axial rotor magnetic suspension module, and adjusts the current values ​​in the radial stator magnetic suspension module and the axial stator magnetic suspension module.

[0017] As a preferred solution of the symmetrical hollow thin-walled magnetic levitation pump described in the present invention, the upper pump shell and the lower pump shell are sealed by ultrasonic welding technology.

[0018] As a preferred solution of the symmetrical hollow thin-walled magnetic levitation pump described in the present invention, the thickness of the thin-wall channel is less than.

[0019] As a preferred solution of the symmetrical hollow thin-walled magnetic levitation pump described in the present invention, the row of radial stator magnetic levitation modules and the row of radial rotor magnetic levitation modules form a group of radial magnetic levitation modules, and the radial magnetic levitation modules are arranged in no less than two groups.

[0020] As a preferred solution of a symmetrical hollow thin-walled magnetic levitation pump described in the present invention, the radial rotor magnetic levitation module and the axial rotor magnetic levitation module include at least one Hall sensor and a communication module for communicating with a microcontroller to transmit signals, and are powered by a built-in micro battery.

[0021] A control method for a magnetic levitation pump with a symmetrical hollow thin-wall configuration, characterized in that the specific steps are as follows:

[0022] S1. Build a blood circulation circuit, and establish a simulated blood path from the inlet to the outlet of the magnetic levitation pump after pre-filling and exhausting;

[0023] S2, system initialization, ensuring that the Hall sensors in the radial rotor magnetic suspension module and the axial rotor magnetic suspension module work normally without obvious zero drift and temperature drift;

[0024] S3. Solve the relationship between the current i(t) of the internal coil of the magnetic levitation motor and the speed ω(t) of the rotor inside the motor: Kirchhoff's voltage law, the circuit equation of the magnetic levitation motor coil is Where R is the internal resistance of the motor, L is the inductance of the motor, and k e is the reverse electromotive force coefficient, V is the voltage, and all of the above are constants;

[0025] S4. Establish a rotational dynamics model. According to Newton's second law, the rotational motion equation of the magnetic levitation blade is: Where b is the damping coefficient, J is the moment of inertia, and k t is the torque coefficient;

[0026] S5, establish current and speed The differential equation relationship of the vector is constructed to design and calculate the state equation of the microcontroller:

[0027]

[0028] Among them, the matrix is an identifiable constant, the matrix When the voltage is constant, it can be treated as a constant;

[0029] S6, the microcontroller collects the voltage signals of the radial rotor magnetic suspension module and the axial rotor magnetic suspension module, and adjusts the current of the axial stator magnetic suspension module in real time according to the state equation of the microcontroller so that the magnetic suspension blade overcomes its own gravity and suspends, and adjusts the current value in the radial stator magnetic suspension module in real time, and applies the rated torque to the magnetic suspension blade by changing the magnetic field strength and magnetic field direction to realize the high-speed rotation of the magnetic suspension blade;

[0030] S7. The high-speed rotating magnetic levitation blades will simulate the suction of blood. The blood flows through the hollow channels and thin-walled channels inside the magnetic levitation blades and then flows out through the liquid outlet pipe.

[0031] Compared with the prior art, the present invention has the following beneficial effects: by optimizing the flow channel design of the pump, a magnetically suspended blade with a symmetrical hollow structure is designed as a rotor, the blade rotor and the lower pump casing form a thin-walled and narrow passage, a dynamic differential equation model based on state space is established, and a microcontroller is used to control the radial and axial stator currents in real time to achieve high-speed rotation and suspension of the rotor blades, which can greatly suppress the turbulence of blood flowing through, making the blood flow more stable and uniform, reducing eddy currents and local high shear areas, improving fluid dynamics characteristics, and reducing hemolysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below in combination with the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0033] Figure 1 This is a schematic diagram of the external structure of a magnetic suspension pump with a symmetrical hollow thin-wall configuration according to the present invention;

[0034] Figure 2 It is a schematic diagram of the assembly structure of a ring seat, a radial stator magnetic suspension module and an axial stator magnetic suspension module of a magnetic suspension pump with a symmetrical hollow thin-wall configuration according to the present invention;

[0035] Figure 3 It is a cross-sectional view of a magnetic suspension pump with a symmetrical hollow thin-wall configuration according to the present invention;

[0036] Figure 4 The control principle diagram of a magnetic suspension pump with a symmetrical hollow thin-wall configuration and a microcontroller of the present invention. DETAILED DESCRIPTION

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0038] Secondly, the present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0039] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0040] The present invention provides a symmetrical hollow thin-walled magnetic levitation pump and a control method thereof, which can effectively reduce blood turbulence and shear force by optimizing the design of the flow channel structure and combining advanced state-space intelligent control technology, thereby significantly reducing hemolysis and improving the safety and effectiveness of VAD equipment.

[0041] Example 1

[0042] Figure 1-Figure 3 The structure diagram of a magnetic suspension pump of a symmetrical hollow thin-walled configuration according to the present invention is shown. Figure 1-Figure 3 The present embodiment is a symmetrical hollow thin-walled magnetic levitation pump, the main body of which includes a housing 100 , magnetic levitation blades 200 and a magnetic levitation drive assembly 300 .

[0043] The housing 100 includes an upper pump shell 110 and a lower pump shell 120 sealed to the upper pump shell 110. In the present embodiment, the upper pump shell 110 and the lower pump shell 120 are sealed by ultrasonic welding. Preferably, barb rings 110a are equidistantly arranged on the outer wall of the liquid inlet pipe of the upper pump shell 110 to make the liquid inlet pipe of the upper pump shell 110 and the connected pipe tighter.

[0044] The magnetic levitation blade 200 is arranged in the shell 100, which has a symmetrical cavity 210, and the position of the magnetic levitation blade 200 between the cavities 210 has a liquid inlet hollow channel H, and the position located outside the cavity 210 forms a thin-walled channel L connected to the liquid inlet hollow channel H with the inner wall of the lower pump shell 120. The present invention optimizes the flow channel design of the pump and designs a magnetic levitation blade 200 with a symmetrical hollow structure as a rotor. The blade rotor and the lower pump shell form a narrow and long passage with a thin wall L, which can greatly suppress the turbulence effect when blood flows through. Preferably, in this embodiment, the thickness of the thin-walled channel L is less than 2 mm.

[0045] Among them, a row of radial stator magnetic levitation modules 320 and a row of radial rotor magnetic levitation modules 340 form a group of radial magnetic levitation modules, and the radial magnetic levitation modules are arranged in no less than two groups. The outer wall of the lower pump shell 120 is provided with a liquid outlet pipe 120a, and the interior thereof is provided with an annular liquid outlet flow channel 120b connected to the thin-walled channel L. The magnetic levitation blade 200 is surrounded by the upper pump shell 110 and the lower pump shell 120 to form a first slow flow cavity M connected to the liquid inlet hollow channel H, and the inner wall of the magnetic levitation blade 200 is located on both sides of the liquid inlet hollow channel H. A symmetrical second slow flow cavity N is opened, which is used to alleviate the turbulence of blood in the hollow channel H of the magnetic levitation blade 200, so that the blood flows more smoothly and evenly.

[0046] The magnetic levitation drive component 300 is used to control and drive the magnetic levitation blade 200 to rotate in the shell 100. In this embodiment, the magnetic levitation drive component 300 includes a ring seat 310 coaxially arranged with the shell 100, a radial stator magnetic levitation module 320 arranged on the side wall of the ring seat 310 and arranged equidistantly, an axial stator magnetic levitation module 330 embedded in the bottom of the ring seat 310, a radial rotor magnetic levitation module 340 arranged on the inner wall of the cavity 210 and arranged equidistantly, an axial rotor magnetic levitation module 350 arranged at the bottom of the cavity 210, and a microcontroller, wherein the microcontroller collects the voltages of the radial rotor magnetic levitation module 340 and the axial rotor magnetic levitation module 350, and adjusts the current values ​​in the radial stator magnetic levitation module 320 and the axial stator magnetic levitation module 330. Preferably, the radial rotor magnetic levitation module 340 and the axial rotor magnetic levitation module 350 include at least one Hall sensor and a communication module for communicating and transmitting signals with the microcontroller, and are powered by a built-in micro battery.

[0047] Example 2

[0048] The present invention also provides a control method for a magnetic levitation pump with a symmetrical hollow thin-wall configuration. The microcontroller is used to control the radial and axial stator currents in real time to realize high-speed rotation and suspension of the rotor blades, which can greatly suppress the turbulence effect when the blood flows through, making the blood flow more stable and uniform. Specifically, the control method of the magnetic levitation pump with a symmetrical hollow thin-wall configuration has the following specific steps:

[0049] S1. Build a blood circulation circuit, and establish a simulated blood path from the inlet to the outlet of the magnetic levitation pump after pre-filling and exhausting;

[0050] S2, system initialization, ensuring that the Hall sensors in the radial rotor magnetic suspension module 340 and the axial rotor magnetic suspension module 350 work normally without obvious zero drift and temperature drift;

[0051] S3. Solve the relationship between the current i(t) of the internal coil of the magnetic levitation motor and the speed ω(t) of the rotor inside the motor: Kirchhoff's voltage law, the circuit equation of the magnetic levitation motor coil is Where R is the internal resistance of the motor, L is the inductance of the motor, and k e is the reverse electromotive force coefficient, V is the voltage, and all of the above are constants;

[0052] S4. Establish a rotational dynamics model. According to Newton's second law, the rotational motion equation of the magnetic suspension blade 200 is: Where b is the damping coefficient, J is the moment of inertia, and k t is the torque coefficient;

[0053] S5, establish current and speed The differential equation relationship of the vector is constructed to design and calculate the state equation of the microcontroller:

[0054]

[0055] The matrix is an identifiable constant, the matrix When the voltage is constant, it can be treated as a constant;

[0056] S6. The microcontroller collects voltage signals of the radial rotor magnetic suspension module 340 and the axial rotor magnetic suspension module 350, and adjusts the current of the axial stator magnetic suspension module 330 in real time according to the state equation of the microcontroller so that the magnetic suspension blade 200 overcomes its own gravity and suspends, and adjusts the current value in the radial stator magnetic suspension module 320 in real time, and applies the rated torque to the magnetic suspension blade 200 by changing the magnetic field strength and magnetic field direction to realize the high-speed rotation of the magnetic suspension blade 200;

[0057] S7. The high-speed rotating magnetic suspension blade 200 sucks in simulated blood, and the blood flows through the hollow channel H and the thin-wall channel L inside the magnetic suspension blade 200 and then flows out through the liquid outlet pipe 120a.

[0058] Although the present invention has been described above with reference to the embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the various features in the embodiments disclosed in the present invention may be used in combination with each other in any manner, and the fact that these combinations are not exhaustively described in this specification is only for the sake of omitting space and saving resources. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A magnetic levitation pump with a symmetrical hollow thin-wall configuration, characterized in that: include: A housing (100) comprising an upper pump housing (110) and a lower pump housing (120) sealedly connected to the upper pump housing (110); A magnetic suspension blade (200) is arranged in the housing (100), and has symmetrical cavities (210), wherein the position of the magnetic suspension blade (200) between the cavities (210) has a liquid inlet hollow channel (H), and the position located outside the cavity (210) forms a thin-walled channel (L) connected to the liquid inlet hollow channel (H) with the inner wall of the lower pump housing (120); A magnetic suspension drive component (300), used for controlling and driving the magnetic suspension blade (200) to rotate in the housing (100); The magnetic suspension blade (200) is surrounded by the upper pump shell (110) and the lower pump shell (120) to form a first slow flow chamber (M) connected to the liquid inlet hollow channel (H), and the inner wall of the magnetic suspension blade (200) is provided with symmetrical second slow flow chambers (N) at positions on both sides of the liquid inlet hollow channel (H).

2. A magnetic levitation pump with a symmetrical hollow thin-wall configuration according to claim 1, characterized in that: Barb rings (110a) are equidistantly arranged on the outer wall of the liquid inlet pipe of the upper pump housing (110).

3. A magnetic levitation pump with a symmetrical hollow thin-wall configuration according to claim 1, characterized in that: The outer wall of the lower pump housing (120) is provided with a liquid outlet pipe (120a), and the interior thereof is provided with an annular liquid outlet flow channel (120b) which is in communication with the thin-wall channel (L).

4. A magnetic levitation pump with a symmetrical hollow thin-wall configuration according to claim 1, characterized in that: The magnetic suspension drive component (300) comprises a ring seat (310) coaxially arranged with the housing (100), a radial stator magnetic suspension module (320) arranged on the side wall of the ring seat (310) and arranged at equal distances, an axial stator magnetic suspension module (330) embedded in the bottom of the ring seat (310), a radial rotor magnetic suspension module (340) arranged on the inner wall of the cavity (210) and arranged at equal distances, an axial rotor magnetic suspension module (350) arranged at the bottom of the cavity (210), and a microcontroller; The microcontroller collects the voltages of the radial rotor magnetic suspension module (340) and the axial rotor magnetic suspension module (350), and adjusts the current values ​​in the radial stator magnetic suspension module (320) and the axial stator magnetic suspension module (330).

5. A magnetic levitation pump with a symmetrical hollow thin-wall configuration according to claim 1, characterized in that: The upper pump casing (110) and the lower pump casing (120) are sealed by using an ultrasonic welding process.

6. A magnetic levitation pump with a symmetrical hollow thin-wall configuration according to claim 1, characterized in that: The thickness of the thin-walled channel (L) is less than 2 mm.

7. A magnetic levitation pump with a symmetrical hollow thin-wall configuration according to claim 4, characterized in that: A row of radial stator magnetic suspension modules (320) and a row of radial rotor magnetic suspension modules (340) form a group of radial magnetic suspension modules, and the radial magnetic suspension modules are arranged in no less than two groups.

8. A magnetic levitation pump with a symmetrical hollow thin-wall configuration according to claim 4, characterized in that: The radial rotor magnetic suspension module (340) and the axial rotor magnetic suspension module (350) include at least one Hall sensor and a communication module, which are used to communicate with a microcontroller and transmit signals, and are powered by a built-in micro battery.

9. A control method for a magnetic levitation pump with a symmetrical hollow thin-wall configuration as claimed in any one of claims 1 to 8, characterized in that: The specific steps are as follows: S1. Build a blood circulation circuit, and establish a simulated blood path from the inlet to the outlet of the magnetic levitation pump after pre-filling and exhausting; S2, system initialization, ensuring that the Hall sensors in the radial rotor magnetic suspension module (340) and the axial rotor magnetic suspension module (350) operate normally without obvious zero drift and temperature drift; S3. Solve the relationship between the current i(t) of the internal coil of the magnetic levitation motor and the speed ω(t) of the rotor inside the motor: Kirchhoff's voltage law, the circuit equation of the magnetic levitation motor coil is Where R is the internal resistance of the motor, L is the inductance of the motor, and k e is the reverse electromotive force coefficient, V is the voltage, and all of the above are constants; S4. Establish a rotational dynamics model. According to Newton's second law, the rotational motion equation of the magnetic suspension blade (200) is: Where b is the damping coefficient, J is the moment of inertia, and k t is the torque coefficient; S5, establish current and speed The differential equation relationship of the vector is constructed to design and calculate the state equation of the microcontroller: Among them, the matrix is an identifiable constant, the matrix When the voltage is constant, it can be treated as a constant. y(t) is the output vector composed of the current Ι(t) and the speed ω(t) of the magnetic levitation motor. S6, the microcontroller collects voltage signals of the radial rotor magnetic suspension module (340) and the axial rotor magnetic suspension module (350), and adjusts the current of the axial stator magnetic suspension module (330) in real time according to the state equation of the microcontroller so that the magnetic suspension blade (200) overcomes its own gravity and suspends, and adjusts the current value in the radial stator magnetic suspension module (320) in real time, and applies rated torque to the magnetic suspension blade (200) by changing the magnetic field strength and magnetic field direction to achieve high-speed rotation of the magnetic suspension blade (200); S7. The high-speed rotating magnetic suspension blade (200) sucks in simulated blood, and the blood flows through the hollow channel (H) and the thin-wall channel (L) inside the magnetic suspension blade (200) and then flows out through the liquid outlet pipe (120a).

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