A shaftless blood pump

Abstract

The present invention discloses a shaftless blood pump comprising a support shell, a stator winding, a bearing outer ring, a bearing inner ring, a rotor conductor, an impeller, and an impeller outer ring. The bearing outer ring is disposed inside the support shell, and the bearing inner ring is disposed inside the bearing outer ring, the bearing inner ring being rotatable inside the bearing outer ring. The impeller is disposed on the inner wall of the impeller outer ring, the outer wall of the impeller outer ring being connected to the inner wall of the bearing inner ring, and the rotor conductor is embedded in the bearing inner ring. The stator winding is disposed on the outer wall of the support shell at a position corresponding to the rotor conductor. The support shell, the bearing outer ring, the bearing inner ring, and the impeller outer ring are coaxially disposed, and the support shell and the bearing outer ring respectively limit the axial ends of the impeller outer ring. The impeller installation angle gradually increases from the outside to the inside, and the impeller tip faces the axis of the impeller outer ring. The present invention solves the problems of existing blood pumps that are prone to hemolysis and high noise. It also has a simple structure, generates only forward velocity blood flow, and has a very low rotational velocity, eliminating the need for front and rear guide vanes.

Description

Technical Field

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

[0002] With the aging of my country's population and changes in people's lifestyles, the incidence of cardiovascular disease has increased dramatically. Almost all cardiovascular diseases ultimately lead to heart failure. Heart failure, also known as HF, is a condition characterized by an inability to adequately drain venous blood from the heart due to impairment of the heart's systolic and / or diastolic function. This leads to blood congestion in the venous system and insufficient arterial perfusion, resulting in a syndrome of cardiac circulatory disorders. Heart transplantation is the best treatment option for end-stage heart failure, but it faces an extreme shortage of donors.

[0003] Artificial heart assist is a treatment for heart failure and an effective alternative to heart transplantation, with promising future applications in the field. Artificial hearts are among the most technologically advanced cardiovascular medical devices. They are high-end products that embody the intersection of multiple disciplines, integrating expertise from a variety of fields, including mechanical design, fluid dynamics optimization, microelectronics, automated control, and surgery. An artificial heart consists of at least a blood pump, a drive unit, a monitoring system, and an energy source. The fluid dynamics unit, or blood pump, is crucial because it determines the pumping capacity of the artificial heart and is closely linked to both short-term and long-term patient complications.

[0004] Existing blood pumps such as Figure 1 As shown, the blood pump includes a pump body arranged in the casing and a driving device arranged outside the pump body. The pump body includes a casing, front guide vanes, rotor conductors and rear guide vanes. The hubs of the front guide vanes, rotor conductors and rear guide vanes adopt an overall streamlined integrated design, and the central axis is used to drive the rotation of the impeller to drive the flow of blood.

[0005] Existing blood pumps have the following defects:

[0006] 1) The blood flow generated by the current blood pump is a rotating blood flow, so front and rear guide vanes are required to ensure the straight flow of blood, which leads to an increase in useless work of the blood pump;

[0007] 2) Current blood pumps include front and rear guide vanes, which increase their size (especially the length of the pump), weight, and installation location. Even when installed in a narrow chest cavity, the burden on the body is increased.

[0008] 3) The use of long artificial blood vessels and complex blood pump structures during installation increases the contact surface between blood and foreign matter, making complications such as thrombosis and infection more likely to occur;

[0009] 4) The inevitable mechanical wear and coupled oscillation of the transmission shaft during the process of rotating to output power will generate considerable noise. Summary of the Invention

[0010] The object of the present invention is to provide a shaftless blood pump to solve the problems of the existing blood pumps being prone to hemolysis and making loud noises, and the pump has a simple structure and does not require front and rear guide vanes.

[0011] The present invention is achieved through the following technical solutions:

[0012] A shaftless blood pump comprises a support shell, a stator winding, a bearing outer ring, a bearing inner ring, a rotor conductor, an impeller and an impeller outer ring;

[0013] The bearing outer ring is arranged inside the support shell, and the bearing inner ring is arranged inside the bearing outer ring, and the bearing inner ring can rotate inside the bearing outer ring;

[0014] The impeller is arranged on the inner wall of the impeller outer ring, the outer wall of the impeller outer ring is connected to the inner wall of the bearing inner ring, the rotor conductor is embedded in the bearing inner ring, and a plurality of rotor conductors are provided, and the plurality of rotor conductors are evenly arranged circumferentially in the bearing inner ring;

[0015] The stator winding is arranged on the outer wall of the support shell at a position corresponding to the rotor conductor;

[0016] The support shell, the bearing outer ring, the bearing inner ring and the impeller outer ring are coaxially arranged, and the support shell and the bearing outer ring respectively limit the axial ends of the impeller outer ring;

[0017] The inner wall of the impeller outer ring is provided with multiple impellers, and the installation angle of the impellers gradually increases from the outside to the inside, that is, the closer the impeller is to the center of the circle, the larger the installation angle is, and the tip of the impeller faces the axis of the impeller outer ring.

[0018] The biggest improvement of the blood pump described in the present invention over existing blood pumps is that it is shaftless, eliminating the mechanical transmission structure of the shaft of a traditional motor. The present invention fixes the impeller to the inner wall of the impeller outer ring, and the impeller outer ring supports the impeller. The impeller rotates with the impeller outer ring, achieving a fundamental change in the mechanical structure of the blood pump described in the present invention compared with the shaft system structure (existing blood pumps), and the power output mode is directly simplified from main engine-drive shaft-impeller to motor-impeller.

[0019] The blood pump propulsion system of the present invention secures the impeller to the rotor conductor within the support housing. The connection between the impeller outer ring and the bearing inner ring can be achieved through the following methods: 1. Molding the impeller outer ring and the bearing inner ring in one piece, or fabricating them using a precision lathe; 2. Inserting the impeller outer ring into the bearing inner ring, creating an interference fit and tightly securing the two; or welding, which can be performed by pressure welding. Under heating or non-heating, pressure is applied to the assembly to cause plastic deformation or melting. Recrystallization and diffusion, among other processes, form metallic bonds between the atoms of the two separated surfaces, connecting them; 3. Two-component epoxy resin or instant adhesive is used at the connection point. Rotation of the rotor conductor generates power. The rotor conductor within the support housing is powered by the stator winding located on the bearing outer ring. When energized, the stator winding generates a rotating magnetic field, which drives the rotor conductor and the entire internal rotor to rotate, thereby pumping blood.

[0020] The support shell, stator winding and bearing outer ring of the present invention constitute the fixed part, and the combination of the bearing inner ring, rotor conductor, impeller and impeller outer ring constitutes the rotating part. The present invention can ensure that blood only contacts the impeller and the inner wall of the impeller outer ring, isolating the blood from the part outside the impeller outer ring.

[0021] Therefore, the shaftless drive structure of the present invention solves the problems that the mechanical transmission of the existing shaft system structure is prone to mechanical wear, heating, hemolysis, coagulation, infection, and high noise.

[0022] In addition, the impeller of the present invention adopts the impeller outer ring to achieve positioning support, and the two ends of the impeller outer ring are axially limited by the support shell and the bearing outer ring respectively, which greatly improves the stability of the rotor rotation. Even at low speed, the rotor can maintain good rotation stability, and the rotation center of the impeller will hardly shift.

[0023] The installation angle corresponding to a certain radius of the blade described in the present invention specifically refers to the angle between the chord length of the cross-section obtained by the cylindrical surface made with the radius and the blade and the bottom surface of the cylinder (rotation surface).

[0024] Furthermore, the inner wall of the impeller outer ring of the present invention is provided with multiple impellers, the tips of the impellers being oriented toward the axis of the impeller outer ring, forming a unique structure in which "the inner ring (including the impeller, the impeller outer ring, and the bearing inner ring) rotates inside the outer ring (the non-rotating portion of the bearing outer ring)." The installation angle of the impeller (blade) of the present invention gradually increases from the outside to the inside, with the installation angle being smallest at the outermost portion (where the impeller and the impeller outer ring are connected) and largest at the innermost portion (the blade tip closest to the axis). The effect of this blade design is that the blood flow velocity generated is mainly axial velocity, with extremely low tangential velocity, and no front or rear guide vanes are required.

[0025] The plane unfolded shape of the blade can be set to rectangular, trapezoidal, mixed trapezoidal, wingtip swept shape and other shapes.

[0026] On the other hand, the larger the installation angle, the greater the resistance the blade encounters, so the blade installation angle at the outer ring of the impeller where the tangential linear velocity is larger should not be too large, and the installation angle is preferably 5° to 45°.

[0027] Furthermore, the outer wall of the bearing outer ring is in close contact with and fixed to the inner wall of the support shell, and the outer wall of the impeller outer ring is in close contact with and fixed to the inner wall of the bearing inner ring.

[0028] Furthermore, the outer ring of the bearing and the inner ring of the bearing are connected by solid self-lubrication.

[0029] The present invention adopts solid self-lubricating bearings to support the rotation of the impeller, does not require lubricating oil for maintenance, and has the advantages of small mechanical vibration, low noise, long service life, etc.

[0030] Furthermore, one end of the support shell extends radially inward to form a first annular baffle, and one end of the bearing outer ring extends radially inward to form a second annular baffle. The first annular baffle and the second annular baffle are respectively used to limit the axial ends of the impeller outer ring.

[0031] Furthermore, the first annular baffle extends outwardly along the axial direction to form a first connecting end, and the second annular baffle extends outwardly along the axial direction to form a second connecting end. The first connecting end and the second connecting end are used to connect to the artificial blood vessel.

[0032] Furthermore, the first connecting end and the outer wall of the first connecting end are both provided with an annular groove, and also include a fixing ring matched with the annular groove.

[0033] Furthermore, the fixing ring is a snap-on metal ring, the inner wall of which is provided with an annular protrusion that matches the annular groove; when the artificial blood vessel is connected to the first connecting end and the second connecting end, the fixing ring is used to fix and seal the artificial blood vessel.

[0034] Furthermore, multiple groups of stator windings are provided, and the multiple groups of stator windings are evenly arranged circumferentially on the outer wall of the support shell. Each group is connected by a wire. The two groups of stator windings connected by the same wire are symmetrically distributed on the circumference, and the wire winding directions of the stator windings symmetrically distributed on both sides of the circumference of the support shell are opposite. The same group of stator windings includes at least one magnetic core and is placed in a straight line. The wires in the same group of stator windings are wound into coils in the same direction on each magnetic core.

[0035] The present invention uses coils wound around a magnetic core, with multiple cores arranged in parallel to form a stator winding. When the coils are energized, the stator windings generate a magnetic field that passes through the cores. Arranging multiple stator windings around the circumference allows the current in each stator winding to vary according to the cosine law, generating a magnetic field that rotates with the axis. This induces current in the rotor conductor, driving the entire rotor.

[0036] The present invention can adjust the number of stator windings, rotor conductors and the number of magnetic cores in a single set of stator windings according to actual needs to obtain appropriate torque and speed.

[0037] Furthermore, three impellers are provided on the inner wall of the impeller outer ring.

[0038] Furthermore, the surface of the impeller and the inner wall of the impeller outer ring, as well as the parts of the inner wall of the bearing outer ring and the support shell that come into contact with the blood are provided with a heparin coating or other coating, which inhibits the formation of coagulation and thrombus and greatly reduces the adhesion of cells on the impeller surface, or tantalum metal plating to form a stable oxide film that does not react with body fluids.

[0039] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0040] 1. The present invention uses a shaftless drive, resulting in higher energy efficiency. Traditional shafted pump-propellants require main shaft transmission and speed change during the propulsion process, resulting in a mechanical efficiency of approximately 50% and even lower energy efficiency. Because the shaftless pump-propellant utilizes direct electromagnetic drive and eliminates redundant mechanical transmission modules, its mechanical efficiency can approach 80%.

[0041] 2. Compared with the traditional shaft system structure, the shaftless pump propulsion technology adopted by the present invention has very low inherent oscillation frequency and mechanical contact noise, which greatly reduces the interference to the human body.

[0042] 3. The present invention is less likely to cause hemolysis due to fever; the contact area with blood is small, and the structure is almost entirely in motion, thus avoiding the deposition of coagulation substances and cells on the impeller and wall. Therefore, the risk of thrombosis is reduced when using the blood pump of the present invention.

[0043] 4. The blood pump of the present invention occupies a small space, is simple to install, and is minimally invasive, meeting the requirements for implantation in the human body. The diameters of the connection points (the first and second connection ends) can be flexibly adjusted according to the thickness of the blood vessels. Furthermore, because the impeller is driven by electromagnetic force, its power source is solely the induced electromagnetic force between the stator winding and the rotor conductor, resulting in excellent sealing, avoiding the structural sealing issues associated with the traditional motor-drive shaft-propeller system.

[0044] 5. The blood pump structure of the present invention is stable and reliable, and can maintain relatively stable rotation at any speed. It can operate normally when placed at any angle, and is not affected by the body's posture when implanted in the human body. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0046] Figure 1 It is a structural diagram of an existing blood pump;

[0047] Figure 2 Schematic diagram of the overall structure of the blood pump of the present invention;

[0048] Figure 3 This is a schematic structural diagram of the fixed portion of the blood pump of the present invention;

[0049] Figure 4 This is a schematic structural diagram of the rotating part of the blood pump of the present invention;

[0050] Figure 5 The structure of the impeller and the impeller outer ring is shown as a schematic diagram Figure 1 ;

[0051] Figure 6 The structure of the impeller and the impeller outer ring is shown as a schematic diagram Figure 2 ;

[0052] Figure 7 Schematic diagram of the impeller structure Figure 1 ;

[0053] Figure 8 Schematic diagram of the impeller structure Figure 2 ;

[0054] Figure 9 It is a structural diagram of a single impeller;

[0055] Figure 10 Schematic diagram of the impeller's trapezoidal shape when unfolded in a plane;

[0056] Figure 11 The figure is a schematic diagram of the arrangement of the stator winding on the outer circumference of the support shell;

[0057] Figure 12 Schematic diagram of the structure of each set of stator windings;

[0058] Figure 13 for Figure 11 Schematic diagram of the current in the three groups of stator windings A, B, and C changing according to the cosine law.

[0059] Markings and corresponding parts names in the accompanying drawings:

[0060] 1-support shell, 2-stator winding, 3-bearing outer ring, 4-fixing ring, 5-bearing inner ring, 6-rotor conductor, 7-impeller, 8-impeller outer ring, 201-first magnetic core, 202-second magnetic core, 203-third magnetic core, 204-fourth magnetic core. DETAILED DESCRIPTION

[0061] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0062] Example 1:

[0063] like Figure 2-13 As shown, a shaftless blood pump includes a support shell 1, a stator winding 2, a bearing outer ring 3, a bearing inner ring 5, a rotor conductor 6, an impeller 7 and an impeller outer ring 8;

[0064] The bearing outer ring 3 is arranged inside the support shell 1, and the bearing inner ring 5 is arranged inside the bearing outer ring 3. The bearing inner ring 5 can rotate inside the bearing outer ring 3;

[0065] The impeller 7 is arranged on the inner wall of the impeller outer ring 8, the outer wall of the impeller outer ring 8 is connected to the inner wall of the bearing inner ring 5, and the rotor conductor 6 is embedded in the bearing inner ring 5. There are multiple rotor conductors 6, and the multiple rotor conductors 6 are evenly arranged in the circumferential direction in the bearing inner ring 5;

[0066] The stator winding 2 is arranged on the outer wall of the support shell 1 at a position corresponding to the rotor conductor 6;

[0067] The support shell 1 , the bearing outer ring 3 , the bearing inner ring 5 and the impeller outer ring 8 are coaxially arranged, and the support shell 1 and the bearing outer ring 3 limit the axial ends of the impeller outer ring 8 respectively.

[0068] In this embodiment, the outer wall of the bearing outer ring 3 is in close contact with and fixed to the inner wall of the support shell 1, and the outer wall of the impeller outer ring 8 is in close contact with and fixed to the inner wall of the bearing inner ring 5; the bearing outer ring 3 and the bearing inner ring 5 are connected by solid self-lubrication.

[0069] In this embodiment, one end of the support shell 1 extends radially inward to form a first annular baffle, and one end of the bearing outer ring 3 extends radially inward to form a second annular baffle. The first annular baffle and the second annular baffle are respectively used to limit the axial ends of the impeller outer ring 8. The first annular baffle extends axially outward to form a first connecting end, and the second annular baffle extends axially outward to form a second connecting end; the outer walls of the first connecting end and the first connecting end are both provided with annular grooves, and also include a fixing ring 4 that cooperates with the annular groove; the fixing ring 4 is a snap-on metal ring, and the inner wall of the snap-on metal ring is provided with an annular protrusion that cooperates with the annular groove.

[0070] That is, in this embodiment, the support shell 1 and the bearing outer ring 3 are both circular boss structures with one end larger than the other end. The large end of the bearing outer ring 3 can be inserted into the inner side of the large end of the support shell 1. The small ends of the support shell 1 and the bearing outer ring 3 are respectively the first connecting end and the second connecting end, which are used to connect to the artificial blood vessel. When the artificial blood vessel is connected to the first connecting end and the second connecting end, the fixing ring 4 is used to fix and seal the artificial blood vessel.

[0071] The assembly process of the blood pump described in this embodiment is as follows:

[0072] The rotor conductor 6 is embedded inside the bearing inner ring 5 and arranged evenly and parallel to the central axis. The impeller 7 and impeller outer ring 8 are integrally formed, ensuring close contact between the outer wall of the impeller outer ring 8 and the inner wall of the bearing inner ring 5. The stator winding 2 is fixed to the outer wall of the support shell 1. After the rotating components (bearing inner ring 5, impeller 7, and impeller outer ring 8) are placed inside the bearing outer ring 3, the support shell 1 is then inserted over the outer ring 3, ensuring close contact between the inner wall of the support shell 1 and the outer wall of the bearing outer ring 3. Solid self-lubrication is used between the bearing inner ring 5 and the bearing outer ring 3, eliminating the need for lubrication such as oil. This connection allows the rotating components to rotate freely within the bearing outer ring 3, while the bearing outer ring 3 and support shell 1 restrict the rotating components' axial position. Furthermore, the rotating components between the bearing outer ring 3 and the bearing inner ring 5 are isolated from blood.

[0073] In this embodiment, the stator winding 2 is energized to generate a magnetic field to rotate the rotor conductor 6 , thereby driving the impeller 7 to rotate.

[0074] Example 2:

[0075] This embodiment is based on Example 1. The stator windings 2 are provided in multiple groups. The multiple groups of stator windings 2 are evenly arranged circumferentially on the outer wall of the support shell 1. Each group is connected by a wire. The two groups of stator windings 2 connected by the same wire are symmetrically distributed on the circumference, and the wire winding directions of the stator windings 2 symmetrically distributed on both sides of the circumference of the support shell 1 are opposite. The same group of stator windings 2 includes at least one magnetic core and is placed in a straight line. The same group of stator winding wires are wound into coils in the same direction on each magnetic core.

[0076] In this embodiment, if Figure 11 As shown, six groups of stator windings 2 are evenly distributed along the outer circumference of the support shell 1, labeled A, B, C, A', B', and C'. Group A is connected to the wires of group A', group B is connected to the wires of group B', and group C is connected to the wires of group C'. The two connected groups of stator windings are symmetrically distributed around the circumference, and the three connection ends A, B, and C can be connected in a triangle or Y shape.

[0077] Each set of stator windings is as follows Figure 12 As shown, it includes: a first magnetic core 201, a second magnetic core 202, a third magnetic core 203, and a fourth magnetic core 204. The first magnetic core 201, the second magnetic core 202, the third magnetic core 203, and the fourth magnetic core 204 are arranged in a straight line. The wires are wound in the same direction on each magnetic core to form coils, that is, each set of coils generates a magnetic field in the same direction after being energized. The wires of the stator windings 2 symmetrically distributed on both sides of the circumference of the support shell 1 are wound in opposite directions, as shown in FIG. Figure 4 As shown, stator winding coils in groups A, B, and C are wound clockwise; stator winding coils in groups A', B', and C' are wound counterclockwise. When all six stator winding groups are energized, a magnetic field is generated that passes through the center of the circle. When the coils are wound clockwise around the magnetic core, a magnetic field with the center pointing downward is generated; when the coils are wound counterclockwise around the core, a magnetic field with the center pointing upward is generated.

[0078] The currents of the three stator windings A, B, and C change according to the cosine law, and their phases differ by 120 degrees. The timing zero point is when the current of group A is the maximum. Figure 13 shown.

[0079] The rotor conductor 6 is embedded in the bearing inner ring 5 using a squirrel-cage structure with six conductor bars evenly distributed. Short-circuiting rings are used to short-circuit the two ends. As the currents in the three stator windings (A, B, and C) vary according to the cosine law, the magnetic field passing through the center of the circle rotates clockwise around the center of the circle. During this rotation, the magnetic field cuts through the rotor conductors, generating an induced electromotive force and an induced current. The rotor conductors carrying the current are acted upon by the magnetic field, generating an electromagnetic force, which generates an electromagnetic torque that drives the bearing inner ring 5 to rotate. The bearing inner ring 5 then connects to the impeller outer ring 8 and, together with the impeller 7, rotates.

[0080] Example 3:

[0081] This embodiment is based on embodiment 1, and a plurality of impellers 7 are provided on the inner wall of the impeller outer ring 8, and the tip of the impeller 7 is directed toward the axis of the impeller outer ring 8, forming an "inner ring (including the impeller, the impeller outer ring and the bearing inner ring) rotating inside the outer ring (the non-rotating part of the bearing outer ring)".

[0082] The installation angle of the impeller 7 tends to increase gradually from the outside to the inside, that is, the closer the impeller 7 is to the center of the circle (the smaller the radius), the larger the installation angle. The installation angle corresponding to a certain radius of the blade specifically refers to the angle between the chord length of the cross-section obtained by the cylindrical surface made with the radius and the blade and the bottom surface of the cylinder (rotating surface); the installation angle of the outermost part (the connection between the impeller 7 and the impeller outer ring 8) is the smallest, and the installation angle of the innermost part (the tip closest to the axis) is the largest. On the other hand, the larger the installation angle, the greater the resistance encountered by the blade, so the installation angle at the outer ring of the blade with a larger circumferential speed should not be too large. It is generally more appropriate to set it within the range of 5° to 45°.

[0083] In this embodiment, if Figure 5-10 As shown, the impeller 7 adopts arc-shaped blades, and the plane unfolded shape of the blades can be set to rectangular, trapezoidal, mixed trapezoidal and wingtip swept shape. Figure 10 This diagram shows a trapezoidal impeller with its blades rotating perpendicular to the axis. The closer the blades are to the center, the slower their circumferential speed, requiring a larger mounting angle to generate sufficient impulse in the blood. The blade mounting angle (i.e., the angle between the blade chord and the rotating plane) increases from the outside inward, increasing as the blades approach the center.

[0084] Rotor conductor 6 drives the impeller in clockwise rotation. The inclined surface of the blades exerts axial pressure on the blood, imparting an impulse to the blood in the direction of flow, transferring kinetic energy and generating axial induced velocity, thereby achieving the blood transport function. In addition to the axial induced velocity, a tangential induced velocity is also generated, oriented in the same direction as the blades' rotation. The combined effect of these two factors results in a twisting effect on the water flow after it passes over the rotating surface of the blades. The blood then flows in a spiral pattern after passing over the rotating surface of the blades. Subsequently, due to the influence of viscous forces between the fluids and the adhesion between the fluid and the surrounding wall, the circumferential velocity of the blood gradually decreases, and the blood flow tends to stabilize.

[0085] Example 4:

[0086] This embodiment is based on any one of Embodiments 1 to 3, in which the surface of the impeller 7 and the inner wall of the impeller outer ring 8, as well as the parts of the inner wall of the bearing outer ring 3 and the support shell 1 that are in contact with blood are provided with a heparin coating to avoid coagulation and thrombosis, or a tantalum metal coating to form a stable oxide film to avoid reaction with body fluids.

[0087] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A shaftless blood pump, characterized in that: It comprises a support shell (1), a stator winding (2), a bearing outer ring (3), a bearing inner ring (5), a rotor conductor (6), an impeller (7) and an impeller outer ring (8); The bearing outer ring (3) is arranged inside the support shell (1), the bearing inner ring (5) is arranged inside the bearing outer ring (3), the bearing inner ring (5) is capable of rotating inside the bearing outer ring (3), and the outer wall of the bearing outer ring (3) is in close contact with and fixed to the inner wall of the support shell (1); The impeller (7) is arranged on the inner wall of the impeller outer ring (8), the outer wall of the impeller outer ring (8) is connected to the inner wall of the bearing inner ring (5), the rotor conductor (6) is embedded in the bearing inner ring (5), and the outer wall of the impeller outer ring (8) is in close contact with and fixed to the inner wall of the bearing inner ring (5); The stator winding (2) is arranged on the outer wall of the support shell (1) at a position corresponding to the rotor conductor (6); The support shell (1), the bearing outer ring (3), the bearing inner ring (5) and the impeller outer ring (8) are coaxially arranged, and the support shell (1) and the bearing outer ring (3) respectively limit the axial ends of the impeller outer ring (8); The inner wall of the impeller outer ring (8) is provided with a plurality of impellers (7), and the impellers (7) generate a blood flow mainly with an axial velocity, so that the shaftless blood pump can realize axial delivery of blood without the need for front and rear guide vanes, and the installation angle of the impeller (7) gradually increases from the outside to the inside, wherein the installation angle at the connection between the impeller (7) and the impeller outer ring (8) is the smallest, and the installation angle of the tip of the impeller (7) closest to the axis is the largest, and the tip of the impeller (7) faces the axis of the impeller outer ring (8).

2. A shaftless blood pump according to claim 1, characterized in that: The bearing outer ring (3) and the bearing inner ring (5) are connected in a solid self-lubricating manner.

3. The shaftless blood pump according to claim 1, characterized in that: One end of the support shell (1) extends radially inward to form a first annular baffle, and one end of the bearing outer ring (3) extends radially inward to form a second annular baffle. The first annular baffle and the second annular baffle are respectively used to limit the axial ends of the impeller outer ring (8).

4. The shaftless blood pump according to claim 3, characterized in that: The first annular baffle extends outwardly along the axial direction to form a first connecting end, and the second annular baffle extends outwardly along the axial direction to form a second connecting end.

5. The shaftless blood pump according to claim 4, characterized in that: The first connecting end and the outer wall of the first connecting end are both provided with an annular groove, and the shaftless blood pump further comprises a fixing ring (4) matched with the annular groove.

6. The shaftless blood pump according to claim 5, characterized in that: The fixing ring (4) is a snap-fit metal ring, and the inner wall of the snap-fit metal ring is provided with an annular protrusion that matches the annular groove.

7. The shaftless blood pump according to claim 1, characterized in that: The stator winding (2) is provided with multiple groups, and the multiple groups of stator windings (2) are evenly arranged in the circumferential direction on the outer wall of the support shell (1). Each group is connected by a wire. Two groups of stator windings (2) connected by the same wire are symmetrically distributed on the circumference, and the winding directions of the wires of the stator windings (2) symmetrically distributed on both sides of the circumference of the support shell (1) are opposite. The same group of stator windings (2) includes at least one magnetic core, and the multiple magnetic cores are placed in a straight line. The wire is wound on each magnetic core in the same direction to form a coil.

8. The shaftless blood pump according to claim 1, characterized in that: Three impellers (7) are provided on the inner wall of the impeller outer ring (8).

9. The shaftless blood pump according to any one of claims 1 to 8, characterized in that: The surface of the impeller (7), the inner wall of the impeller outer ring (8), and the blood-contacting portions of the inner wall of the bearing outer ring (3) and the support shell (1) are all provided with a heparin coating or a tantalum metal plating layer.

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