A dynamic pressure impeller-converging internal thrust bearing and artificial heart

Abstract

A dynamic pressure impeller-converging inner channel thrust bearing and artificial heart are disclosed. The impeller-converging inner channel thrust bearing and a tilting pad diaphragm dynamic pressure sliding bearing are integrated into one unit, allowing the rotor to rotate and suspend within the stator cavity of the artificial heart. The dynamic pressure impeller-converging inner channel thrust bearing features a tilting pad diaphragm dynamic pressure bearing surface in the radial direction and a large slope dynamic pressure bearing surface in the axial direction. The large and small slope impellers and the converging inner channel are designed on the artificial heart, utilizing the interaction between the large and small slope impellers and the stator to generate multiple sets of blood converging wedges to support the operation of the artificial heart rotor. Simultaneously, the converging inner channel is opened inside the artificial heart, which has both a high pressure relief effect and a thrust bearing cavity pressure protection effect, reducing the compression damage of the axial thrust bearing on the blood and improving the resistance of the hydraulically suspended artificial heart pump to hemolysis, thrombosis, and bleeding. This design facilitates the formation of a dynamic pressure liquid film to generate dynamic pressure, which is beneficial for maintaining the stability and long-term operation of the heart pump rotor.

Description

Technical Field

[0001] This invention is a cross-disciplinary technology combining mechanical manufacturing and medical engineering, mainly in the field of artificial heart technology, and specifically relates to a dynamic pressure impeller-converging inner channel thrust bearing and an artificial heart. Background Technology

[0002] The heart, one of the most vital organs in the human body, pumps blood to all organs and tissues through rhythmic contractions and relaxations. This provides oxygen and nutrients while removing metabolic waste products, maintaining normal cellular metabolism and function. If the heart's contraction and relaxation functions are impaired due to various disease factors, its pumping function weakens, leading to an absolute or relative decrease in cardiac output, which fails to meet the body's needs—a condition known as heart failure. Traditional drug treatments for heart failure have limitations and are often ineffective; orthotopic heart transplantation remains one of the most effective treatments. However, the global shortage of heart donors far exceeds the needs of patients. Therefore, artificial hearts—mechanical devices made of various materials that can completely or partially replace the pumping function of the natural heart—can effectively help patients transition through transplantation, recover during the recovery period, and even have long-term implantation to meet their heart's pumping function.

[0003] Existing artificial heart pump technologies, such as patent CN 112587793 A which discloses a heart pump supported by ball bearings, have the disadvantage that the ball bearings periodically squeeze the blood, creating compressive stress and shear stress fields, which cause blood damage problems such as hemolysis and thrombosis in the artificial heart pump. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention aims to provide a dynamic pressure impeller-converging inner channel thrust bearing and an artificial heart. Based on the theory of hydrodynamic lubrication, it utilizes the relative motion between the impeller with large and small slopes and the blood to generate axial thrust to support the artificial heart rotor. At the same time, it utilizes the pressure relief effect of the converging inner channel to protect the blood in the high-pressure area. The supporting force generated by the tilting pad radial bearing supports the artificial heart rotor radially, and the driving force generated by the coil and permanent magnet drives the rotor to suspend and pump blood within the stator cavity of the artificial heart. The dynamic pressure impeller-converging inner channel thrust bearing of the present invention not only generates axial supporting force to support the artificial heart rotor axially, but also reduces the compression of blood by the axial thrust bearing, while ensuring smooth blood flow at the bottom of the artificial heart. This solves the problems of hemolysis and thrombosis that affect the safety of blood pumping in existing artificial heart pumps.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] A dynamic pressure impeller-converging internal thrust bearing includes a stator 2-1 and a rotor 2-2 configured therewith;

[0007] The stator 2-1 body has a converging internal channel 11. The blood inlet 12 of the converging internal channel 11 is located at the bottom of the stator 2-1, and the blood outlet 13 of the internal channel is located at the blood outlet 7 of the stator 2-1. The blood inlet 12 of the internal channel is large, and the blood outlet 13 of the internal channel is small. The bleeding path of the entire converging internal channel 11 is converging.

[0008] The rotor 2-2 has an integrated impeller 22 in the axial direction. The lower impeller 22-2 of the impeller 22 has a small slope 2-3 in the high pressure zone and a large slope 2-4 in the low pressure zone, forming a dynamic pressure impeller structure with a large and small slope design.

[0009] The edges of the impellers of the internal duct blood inlet 12, internal duct bleeding inlet 13, small slope 2-3, and large slope 2-4 are all provided with smooth rounded corners.

[0010] A dynamic pressure impeller-converging inner channel thrust bearing artificial heart includes a housing 1; the inner cavity of the housing 1 is provided with a blood outlet 7 and a blood inlet 9, with the blood inlet 9 located above the housing 1 and the blood outlet 7 located on the side of the housing 1; a central shaft 8 is provided at the center of the bottom of the inner cavity of the housing 1, and the central shaft 8 is an integral structure with the heart pump housing 1; a motor stator coil 4 is assembled inside the central shaft 8, and the motor stator coil 4 is coaxial with the central shaft 8;

[0011] The housing 1 is axially integrated with the stator 2-1 of the dynamic pressure impeller-converging inner channel thrust bearing 5 on its bottom inner wall; the stator 2-1 has a converging inner channel 11 inside; the housing 1 is radially provided with a tilting pad diaphragm dynamic pressure sliding bearing 6, and the rotor of the dynamic pressure impeller-converging inner channel thrust bearing 5 and the tilting pad diaphragm dynamic pressure sliding bearing 6 is designed as an integral rotor 2-2. The rotor 2-2 has a motor rotor permanent magnet 3 embedded inside, and an impeller 22 is integrally designed above the rotor 2-2. A longitudinally through flow channel is formed between the central shaft 8 and the dynamic pressure impeller-converging inner channel thrust bearing 5.

[0012] The telescopic rod 6-3 of the tilting tile diaphragm dynamic pressure sliding bearing 6 is fixed on the inner wall of the housing 1. The two ends of the back of the tilting tile 6-1 of the tilting tile diaphragm dynamic pressure sliding bearing 6 are hinged to the telescopic rod 6-3 and can swing. The front part of the tilting tile 6-1 is arc-shaped. The two ends of the front part of the tilting tile 6-1 are connected to the soft membrane 6-2 to form a converging blood cavity in the radial direction, generating radial support force to support the rotor 2-2.

[0013] The number of tiltable tiles 6-1 is greater than three.

[0014] The housing 1 is divided into an upper shell and a lower shell. The contact surfaces of the upper shell and the lower shell have the same shape, and the upper shell and the lower shell are relatively fixed and sealed by a detachable connection.

[0015] The impeller 22 adopts a semi-open upper and lower double impeller design. The upper impeller 22-1 with large blades is the main impeller, and the lower impeller 22-2 with small blades is the dynamic pressure impeller. It has a small slope 2-3 in the high pressure area and a large slope 2-4 in the low pressure area.

[0016] A spiral blood-pressure chamber 15 with a circular cross-section is formed between the blood outlet 7 and the outlet of the upper impeller 22-1.

[0017] A non-tapered, straight-cone blood-suction chamber 16 is formed between the blood inlet 9 and the upper impeller 22-1 inlet.

[0018] The permanent magnets 3 of the motor rotor are arranged radially and uniformly in the rotor 2-2.

[0019] Compared with the prior art, the present invention has the following beneficial technical effects:

[0020] 1. In this invention, the dynamic pressure impeller-converging inner channel thrust bearing 5 utilizes impellers with varying slopes 22-2, employing a dynamic pressure impeller structure with a small slope 2-3 in the high-pressure zone and a large slope 2-4 in the low-pressure zone. During rotation, the dynamic pressure impeller forms a converging wedge-shaped blood inner cavity with the stator 2-1, generating axial dynamic pressure to support the artificial heart rotor. This design not only generates axial levitation force to support rotor rotation but also promotes blood flow at the bottom through the large and small slope impellers 22-2, ensuring unobstructed blood flow and reducing the risk of thrombosis.

[0021] 2. Dynamic pressure impeller - converging inner channel thrust bearing 5 has a converging inner channel 12 at the bottom of stator 2-1. This design reduces the squeezing damage to blood caused by the axial thrust bearing; the high-pressure blood relief port formed by the converging inner channel not only preserves the dynamic pressure of blood inside the thrust bearing, but also reduces the squeezing force of the thrust bearing on the blood by releasing blood, thus promoting blood flow and effectively reducing the heart pump's ability to form thrombi.

[0022] 3. The tilting pad diaphragm hydrodynamic sliding bearing 6 has multiple tilting pads 6-2 in the radial direction, which facilitates the formation of multiple hydrodynamic liquid films with the rotor 22 to generate dynamic pressure, increasing the radial support force. At the same time, it increases the gap of the radial hydrodynamic bearing surface, reduces the radial squeezing force on the blood, and effectively adjusts the position of the rotor 22 in the inner cavity of the stator 2-1, which is beneficial to maintaining the stability and long-term operation of the heart pump rotor.

[0023] 4. The tilting pad diaphragm hydrodynamic sliding bearing 6 can automatically adjust the wedge-shaped inlet width formed by the tilting pad 6-1 and the soft diaphragm 6-2 according to the magnitude of the blood hydrodynamic pressure, which is beneficial for forming radial support force. At the same time, multiple tilting pads can form multiple blood convergence wedges, increasing the radial hydrodynamic support force and ensuring that the blood hydrodynamic pressure is kept below an upper limit that does not damage the blood. It also facilitates the formation of a stable hydrodynamic liquid film to generate sufficient dynamic pressure to support the operation of the artificial heart rotor. Simultaneously, it increases the radial blood flow channel clearance, increases the thickness of the blood hydrodynamic layer, and reduces the squeezing damage to the blood. The combination of multiple sets of tilting pads and soft diaphragms ensures that the rotor can maintain a convergence wedge structure and an appropriate distance from the outer shell even with slight shaking. Within certain limits, this ensures that the artificial heart can operate normally under external interference, reducing the harm to the patient caused by unstable blood pumping by the artificial heart pump. This is beneficial for maintaining the long-term stable operation of the heart pump rotor.

[0024] 5. The housing 1 is divided into an upper shell and a lower shell, which are relatively fixed and sealed through a detachable connection method. It has the characteristics of being easy to manufacture, simple in structure and easy to assemble.

[0025] 6. The permanent magnets 3 of the motor rotor are arranged radially and uniformly. The specific number and size of the permanent magnets can be determined based on the designed dynamic pressure impeller-converging inner channel thrust bearing 5 and the power of the artificial heart. The electromagnetic design of the artificial heart drive motor is characterized by its simplicity, flexibility, and ability to provide different ranges of electromagnetic torque and motor speeds at different frequencies.

[0026] 7. Impeller 22 adopts a semi-open upper and lower double impeller design, which is simple to process and causes less shear damage to blood, thus protecting blood to the greatest extent.

[0027] 8. The large and small slope impeller 22-2 of the present invention uses the liquid dynamic pressure generated during the rotation to support the artificial heart rotor, and at the same time has the functions of pumping blood and promoting blood flow. It not only increases the blood dynamic pressure support force at the bottom in the axial direction, but also increases the space for blood flow at the bottom, reduces the squeezing force on the blood, and avoids blood damage caused by excessive squeezing. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the longitudinal cross-section of the artificial heart of the present invention.

[0029] Figure 2A This is a schematic diagram of the structure of part 1 of the housing of the present invention.

[0030] Figure 2B A schematic diagram of the radial structure of section 11 of the convergent inner channel.

[0031] Figure 3 A is a schematic diagram of the artificial heart rotor part of the present invention.

[0032] Figure 3 B is a schematic diagram of the impeller structure with large and small slopes at the bottom of the rotor of the present invention.

[0033] Figure 4 This is a schematic diagram of the structure of the tilting membrane hydrodynamic sliding bearing 6.

[0034] In the diagram: 1. Shell; 2-1. Stator; 2-2. Rotor; 2-3. Small slope; 2-4. Large slope; 3. Motor rotor permanent magnet; 4. Motor stator coil; 5. Dynamic pressure impeller-converging inner channel thrust bearing; 6. Tilting pad diaphragm dynamic pressure sliding bearing; 6-1. Tilting pad; 6-2. Soft diaphragm; 6-3. Telescopic slider; 7. Blood outlet; 8. Central shaft; 9. Blood inlet; 11. Converging inner channel; 12. Inner channel blood inlet; 13. Inner channel bleeding outlet; 15. Spiral blood pressure chamber; 16. Non-tapered straight conical blood suction chamber; 22. Impeller; 22-1. Upper impeller; 22-2. Lower impeller. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings.

[0036] A dynamic pressure impeller-converging internal thrust bearing includes a stator 2-1 and a rotor 2-2 configured therewith;

[0037] like Figure 1 , Figure 2A , Figure 2B As shown, the stator 2-1 body has three converging internal channels 11 designed at its bottom. The blood inlet 12 of each converging internal channel 11 is located at the bottom of the stator 2-1, and the blood outlet 13 is located at the blood outlet 7 of the stator 2-1. The blood inlet 12 is large, and the blood outlet 13 is small, resulting in a converging bleeding path throughout the converging internal channels 11. Blood flows in from the three blood inlets 12, passes through the internal channels 11, and converges into the same blood outlet 13. The converging design of the converging internal channels 11 effectively relieves the high-pressure blood flow at the bottom. Simultaneously, the design of the large inlet 12 and small outlet 13 ensures pressure at the blood inlet 12, allowing normal blood flow within the internal channels 11. This design maintains pressure on the blood at the bottom while preventing hemolysis caused by high pressure. In this embodiment of the invention, the dimensions of the converging internal channel 11, the blood inlet 12, and the bleeding outlet 13 are determined according to the power and pumping volume of the specific artificial heart, and the specific manufacturing method can refer to any existing technology.

[0038] like Figure 3 A, Figure 3As shown in b, the rotor 2-2 has an integrated impeller 22 in the axial direction. The lower impeller 22-2 has a small slope 2-3 in the high-pressure zone and a large slope 2-4 in the low-pressure zone, forming a dynamic pressure impeller structure with large and small slopes. During rotation, the dynamic pressure impeller forms a converging wedge-shaped blood cavity with the stator 2-1 and generates an axial levitation force to support the rotor 2-2 in the pump body without contacting the pump body. In addition to generating levitation force, the large and small slope impellers can also guide the flow. After the thrust bearing rotor 2-2 rotates, it will guide the fluid to flow outward, promote blood return, increase the scrubbing of the surfaces of the bearing rotor 2-2 and bearing stator 2-1, and reduce the risk of blood stagnation and thrombosis.

[0039] The edges of the impellers of the internal duct blood inlet 12, internal duct bleeding inlet 13, small slope 2-3, and large slope 2-4 are all provided with smooth rounded corners.

[0040] A dynamic pressure impeller-converging internal thrust bearing artificial heart includes a housing 1; as Figure 1 As shown in Figure 2, the inner cavity of the housing 1 is provided with a blood outlet 7 and a blood inlet 9, with the blood inlet 9 located above the housing 1 and the blood outlet 7 located on the side of the housing 1; a central shaft 8 is provided at the center of the bottom of the inner cavity of the housing 1, and the central shaft 8 is an integral structure with the heart pump housing 1; a motor stator coil 4 is assembled inside the central shaft 8, and the motor stator coil 4 is coaxial with the central shaft 8.

[0041] like Figure 1 , Figure 4 As shown, the inner wall of the bottom of the housing 1 is integrated with the stator 2-1 of the dynamic pressure impeller-converging inner channel thrust bearing 5 in the axial direction; the stator 2-1 has a converging inner channel 11 inside; the housing 1 is provided with a tilting diaphragm dynamic pressure sliding bearing 6 in the radial direction.

[0042] like Figure 1 , Figure 2A , Figure 2B As shown, the converging internal channel 11 has a large diameter at the blood inlet 12 and a small diameter at the blood outlet 13. This internal channel design with a large inlet and a small outlet can maintain the pressure of the blood flowing through the internal channel, which facilitates the blood inside the thrust bearing to support the thrust bearing rotor 2-2, and can also relieve pressure, protecting the blood from damage caused by excessive pressure.

[0043] like Figure 1As shown, the rotor 2-2 is an integral unit of the dynamic pressure impeller-converging inner channel thrust bearing 5 and the tilting pad diaphragm dynamic pressure sliding bearing 6. The rotor 2-2 contains a motor rotor permanent magnet 3. An impeller 22 is integrally designed above the rotor 2-2. A longitudinally continuous flow channel is formed between the central shaft 8 and the dynamic pressure impeller-converging inner channel thrust bearing 5. During the rotation of the rotor 2-2 and the centrifugal pumping process, the fluid flowing in from the blood inlet 9 is guided by the conical tip of the central shaft 8, partially entering the longitudinally continuous flow channel and flowing axially towards the dynamic pressure impeller-converging inner channel thrust bearing 5 and radially towards the tilting pad diaphragm dynamic pressure sliding bearing 6. Part of the fluid flows into the inner channel bleeding outlet 13 through the converging inner channel 11 at the bottom of the housing, and then flows out from the blood outlet 7. Part of the fluid flows towards the surface of the impeller 22, centrifugally flowing along the impeller 22 to the blood outlet 7, thereby increasing the blood pressure at the blood outlet 7 and perfusing blood to the patient's organs and tissues throughout the body.

[0044] like Figure 1 , Figure 4 As shown, the telescopic rod 6-3 of the tilting tile diaphragm hydrodynamic sliding bearing 6 is fixed to the inner wall of the housing 1. The two ends of the back of the tilting tile 6-1 of the tilting tile diaphragm hydrodynamic sliding bearing 6 are hinged to the telescopic rod 6-3 and can swing at a certain angle. The front part of the tilting tile 6-1 is designed as an arc surface, and the two ends of the front part of the tilting tile 6-1 are connected to the soft membrane 6-2. The connection method can be fixed by glue or other methods. The soft membrane 6-2 can take on any shape as the tilting tile 6-1 swings. The material of the soft membrane 6-2 can be made of silicone polycarbonate polyurethane material. The tilting tile 6-1 and other components of the artificial heart can be made of titanium alloy or nickel-titanium alloy. In the design and manufacturing, the number of tilting tiles 6-1 is greater than three, and the number of soft membranes 6-2 changes with the number of tilting tiles 6-3. Multiple sets of tilting pads oscillate and form multiple converging wedges on the outer surface of rotor 2-2, generating a levitation force in the radial direction. This force is directly applied to the bearing rotor 2-2, causing rotor 2-2 to suspend within the pump body without contacting it. During the rotation of rotor 2, the tilting pads 6-1 oscillate at a certain angle with the extension and retraction of sliding rod 6-3, driving the movement of diaphragm 6-2. Together with diaphragm 6-2, the tilting pads 6-1 and rotor 2-2 form a converging blood cavity in the radial direction, generating radial support force to support rotor 2-2. The tilting pad diaphragm hydrodynamic sliding bearing 6 increases the number of effective converging wedges in the artificial heart cavity and increases the clearance of the hydrodynamic bearing surface, solving the problems of hemolysis and thrombosis in existing artificial heart pumps.

[0045] The housing 1 is divided into an upper housing and a lower housing. The contact surfaces of the upper and lower housings have completely identical shapes, and the upper and lower housings are relatively fixed and sealed through a detachable connection method. For example, existing technologies such as screw connections can be used. The heart pump housing 1 adopts a volute shape, but cylindrical, conical, or other shapes suitable for blood centrifugation can also be used.

[0046] The impeller 22 adopts a semi-open upper and lower double impeller design. The semi-open structure is simple to process and causes less shear damage to the blood. The upper impeller 22-1 has large blades and is the main impeller, which has the function of drawing blood from the blood inlet 9 and discharging blood from the blood outlet 7. The lower impeller 22-2 has small blades and is a dynamic pressure impeller. It has a small slope 2-3 in the high pressure area and a large slope 2-4 in the low pressure area. It has the function of generating axial dynamic pressure with the stator 2-1 and the blood, and supporting the rotor 2-2.

[0047] A spiral blood-pressure chamber 15 with a circular cross-section is formed between the blood outlet 7 and the outlet of the upper impeller 22-1. The blood flowing out of the upper impeller 22-1 is collected and transported to the blood outlet 7, reducing the blood flow velocity at the impeller 22, converting kinetic energy into static pressure energy, and eliminating the rotation of the blood flowing out of the rotating impeller 22 to avoid hydraulic loss.

[0048] A non-tapered, straight conical blood suction chamber 16 is formed between the blood inlet 9 and the inlet of the upper impeller 22-1. The flow rate changes uniformly from the blood inlet 9 to the impeller 22 inlet, ensuring a consistent and stable flow to the impeller 22 inlet. Because the heart pump structure is relatively small, the taper of the blood suction chamber is not large. Furthermore, for ease of manufacturing, the blood suction chamber is directly machined into a non-tapered, straight conical blood suction chamber 16.

[0049] The permanent magnets 3 of the motor rotor are arranged radially and uniformly in the rotor 2-2. The motor of the permanent magnets 3 of the motor rotor is a brushless DC motor with a position control feedback system, which constantly monitors the position of the thrust bearing 5 of the dynamic pressure impeller-converging inner channel and makes appropriate adjustments to ensure stable operation. This part can be implemented with reference to existing technology and is not specifically limited in this invention.

[0050] The working principle of this invention is as follows: Blood enters the heart pump from the blood inlet 9, passes through the guide at the conical top of the central shaft 8, flows through the impeller 22 and flows axially to the thrust bearing 5 of the dynamic pressure impeller-converging inner channel and radially to the tilting pad diaphragm dynamic pressure sliding bearing 6. Driven by a brushless motor consisting of a permanent magnet 3 on the rotor and a current-carrying stator coil 4 inside the central shaft 8, the rotor rotates, forming a radial blood support force in the radial direction, isolating the stator 2-1 and rotor 2-2 of the tilting diaphragm hydrodynamic sliding bearing 6. Similarly, the rotation of rotor 2-2 drives the blood in the axial direction to form an axial blood support force, isolating the stator 2-1 and rotor 2-2 of the axial hydrodynamic impeller-converging inner channel thrust bearing 5. This achieves complete hydrodynamic suspension of rotor 2-2 of the artificial heart. The fully hydrodynamically suspended rotor 2-2 drives the blood to collect and transport to the blood outlet 7 through the upper impeller 22-1, and pumps and supports the suspension through the lower impeller 22-2, exporting the blood deposited inside the hydrodynamic impeller-converging inner channel thrust bearing 5 to the upper part of the inner cavity of the heart pump housing 1, thus realizing the output of blood. Some blood will also flow into the bleeding outlet 13 of the internal channel through the three converging internal channels 11 at the bottom of the stator 2-1, and then flow out through the blood outlet 7, ensuring blood flow and improving the artificial heart pump's ability to resist hemolysis and thrombosis.

[0051] The dynamic pressure impeller-converging inner channel thrust bearing 5 can automatically adjust the blood volume and flow rate entering the convergent wedge according to the magnitude of the blood dynamic pressure at the bottom of the artificial heart. This not only ensures that the blood dynamic pressure is kept below an upper limit that does not damage the blood, but also facilitates the formation of a stable dynamic pressure liquid film to generate sufficient dynamic pressure to support the operation of the artificial heart rotor. Simultaneously, it increases the thickness of the blood dynamic pressure layer, reducing the squeezing damage to the blood. Based on the impeller structure with varying slopes, multiple sets of convergent wedges can be formed during the operation of the artificial heart. The tilting pad 6-1 and soft diaphragm 6 of the tilting pad diaphragm dynamic pressure sliding bearing 6, in conjunction with the rotor, can form multiple sets of radial convergent wedges. This ensures that the rotor maintains a convergent wedge structure and an appropriate distance from the outer shell even with slight vibrations, guaranteeing the normal operation of the heart pump under external interference within certain limits. This structural design of a dynamic pressure impeller-converging inner channel thrust bearing artificial heart reduces the harm to the patient caused by unstable blood pumping by the artificial heart pump and is beneficial for maintaining the long-term stable operation of the heart pump rotor.

Claims

1. A dynamic pressure impeller-converging channel thrust bearing characterized by, It comprises a stator (2-1) and a rotor (2-2) arranged in the stator; the stator (2-1) is provided with a converging inner channel (11) in the body, the inner channel inlet (12) of the converging inner channel (11) is arranged on the upper surface of the bottom of the stator (2-1), and the inner channel outlet (13) is arranged at the blood outlet (7) of the stator (2-1); the inner channel inlet (12) is large, the inner channel outlet (13) is small, and the blood outlet path of the whole converging inner channel (11) is converging; The rotor (2-2) is integrally designed with an impeller (22) in the axial direction, the impeller (22) is designed with a half-open upper and lower double-impeller, the upper impeller (22-1) is a main impeller with large blades, and the lower impeller (22-2) is a dynamic pressure impeller with small blades, which has a large and small slope surface structure with a small slope surface (2-3) in a high pressure area and a large slope surface (2-4) in a low pressure area.

2. A dynamic pressure impeller-convergent channel thrust bearing according to claim 1, characterized in that The inner channel inlet (12), the inner channel outlet (13), the small slope surface (2-3) and the large slope surface (2-4) are all provided with smooth fillets.

3. An artificial heart based on the dynamic pressure impeller-convergent channel thrust bearing according to claim 1 or 2, comprising a housing (1), the inner cavity of the housing (1) is provided with a blood outlet (7) and a blood inlet (9), and the blood inlet (9) is located above the housing (1), and the blood outlet (7) is located on the side of the housing (1); characterized in that, A central shaft (8) is arranged at the bottom center of the inner cavity of the shell (1), and the central shaft (8) and the heart pump shell (1) are an integral structure; a motor stator coil (4) is arranged in the central shaft (8), and the motor stator coil (4) is coaxial with the central shaft (8); The bottom inner wall of the shell (1) is integrally designed with the stator (2-1) of the dynamic pressure impeller-converging inner channel thrust bearing (5) in the axial direction; the stator (2-1) is provided with a converging inner channel (11) in the body; the shell (1) is provided with a tilting pad film dynamic pressure sliding bearing (6) in the radial direction, the rotor of the dynamic pressure impeller-converging inner channel thrust bearing (5) and the tilting pad film dynamic pressure sliding bearing (6) are designed as an integrated rotor (2-2), the rotor (2-2) is embedded with a motor rotor permanent magnet (3), and the rotor (2-2) is integrally designed with an impeller (22) above; a longitudinal through flow channel is formed between the central shaft (8) and the dynamic pressure impeller-converging inner channel thrust bearing (5); The telescopic pull rod (6-3) of the tilting pad film dynamic pressure sliding bearing (6) is fixed on the inner wall of the shell (1), the two ends of the back of the tilting pad (6-1) of the tilting pad film dynamic pressure sliding bearing (6) are hinged to the telescopic pull rod (6-3) and can swing; the front of the tilting pad (6-1) is arc-shaped, the front of the tilting pad (6-1) is connected with the soft film (6-2) to form a converging blood inner cavity in the radial direction, generate radial support force, and support the rotor (2-2).

4. A dynamic pressure impeller-convergent diffuser thrust bearing artificial heart according to claim 3, characterized in that The number of the tilting pads (6-1) is greater than three.

5. A dynamic pressure impeller-convergent diffuser thrust bearing artificial heart according to claim 3, characterized in that The shell (1) is divided into an upper shell and a lower shell, the contact surface of the upper shell and the lower shell is completely consistent, and the upper shell and the lower shell are relatively fixed and sealed by a detachable connection mode.

6. A dynamic pressure impeller-convergent diffuser thrust bearing artificial heart according to claim 3, characterized in that The blood outlet (7) and the outlet of the upper impeller (22-1) form a spiral blood compression chamber (15) with a circular cross section.

7. A dynamic pressure impeller-convergent diffuser thrust bearing artificial heart according to claim 3, characterized in that The blood inlet (9) and the inlet of the upper impeller (22-1) form a straight taper blood suction chamber (16) without taper.

8. A dynamic pressure impeller-convergent diffuser thrust bearing artificial heart according to claim 3, characterized in that The motor rotor permanent magnets (3) are uniformly arranged in the rotor (2-2) in a radial manner.

Images