Drive device and blood pump

Abstract

The invention relates to a driving device and a blood pump, the driving device is used for driving an impeller to rotate, the driving device comprises a shell assembly and a rotating shaft, and the shell assembly is provided with a mounting hole; the rotating shaft comprises a first shaft section which is used for being fixedly connected with the impeller and can rotationally penetrate through the mounting hole, an arc-shaped convex surface is arranged in the circumferential direction of the first shaft section, at least part of the arc-shaped convex surface is located in the mounting hole, the inflection point of the arc-shaped convex surface is opposite to the hole wall of the mounting hole, and the first shaft section is fixedly connected with the impeller. The gap between the arc-shaped convex surface and the hole wall of the mounting hole is minimum; and when the first shaft section is in contact with the hole wall of the mounting hole, the inflection point of the arc-shaped convex surface is in contact with the hole wall of the mounting hole. The rotating shafts of the blood pump and the driving device are low in abrasion degree.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a drive device and a blood pump. Background Technology

[0002] An intravascular blood pump is a blood-pumping device that can be inserted into a patient's heart through a blood vessel. The pump is placed inside the opening of the heart valve, allowing blood to flow through the pump and into the artery. The pump consists of a drive unit and an impeller. The impeller is fixed to the shaft of the drive unit, which drives the impeller to rotate. However, traditional drive units often experience significant wear on their shafts. Summary of the Invention

[0003] Therefore, it is necessary to provide a drive device and blood pump with low shaft wear.

[0004] A driving device for driving an impeller to rotate, characterized in that the driving device comprises: The housing assembly is provided with mounting holes; and The rotating shaft includes a first shaft segment for fixed connection with the impeller and rotatably passing through the mounting hole. The first shaft segment has an arcuate convex surface in the circumferential direction. At least a portion of the arcuate convex surface is located in the mounting hole. The inflection point of the arcuate convex surface is opposite to the hole wall of the mounting hole, and the gap between the arcuate convex surface and the hole wall of the mounting hole is minimal at the inflection point of the arcuate convex surface. When the first shaft segment contacts the hole wall of the mounting hole, the inflection point of the arcuate convex surface contacts the hole wall of the mounting hole.

[0005] In one embodiment, the distance H between the inflection point of the arcuate convex surface and the plane containing the opening of the mounting hole near the impeller end along the axial direction of the first shaft segment is defined as H, and the value of H is in the range of H≤0.2mm.

[0006] In one embodiment, the arcuate convex surface has a first arcuate portion located within the mounting hole, along the axial direction of the first shaft segment and toward the impeller, the distance from the first arcuate portion to the axis of the first shaft segment gradually increases, and the inflection point of the arcuate convex surface is located on the first arcuate portion.

[0007] In one embodiment, the first shaft segment has a first column portion housed in the housing assembly and a second column portion connected to the first column portion and located outside the housing assembly. The second column portion is used to be fixedly connected to the impeller. The second column portion and the first column portion are coaxially arranged. The circumferential surface of the second column portion near the first column portion is a cylindrical surface. The arcuate convex surface is located at the end of the first column portion near the second column portion. The arcuate convex surface is connected to the cylindrical surface. The connection point between the arcuate convex surface and the cylindrical surface is the inflection point of the arcuate convex surface. The inflection point of the arcuate convex surface is flush with the plane of the opening of the mounting hole near the impeller end. Alternatively, the arcuate convex surface may further have a second arcuate surface connected to the first arcuate surface, the second arcuate surface and the first arcuate surface being arranged along the axial direction of the first shaft segment, and the connection point between the second arcuate surface and the first arcuate surface being the inflection point of the arcuate convex surface; along the axial direction of the first shaft segment and toward the impeller, the distance from the second arcuate surface to the axis of the first shaft segment gradually decreases.

[0008] In one embodiment, the wall of the mounting hole is provided with an arc-shaped concave portion opposite to the arc-shaped convex surface. The curvature of the concave portion is smaller than that of the arc-shaped convex surface. When the first shaft segment contacts the wall of the mounting hole, the inflection point of the arc-shaped convex surface contacts the concave portion.

[0009] In one embodiment, the mounting hole has a first hole portion and a second hole portion that are connected. The diameter of the first hole portion is constant, and the diameter of the second hole portion gradually decreases along the direction close to the first hole portion. The first shaft segment passes through the first hole portion and the second hole portion. The inflection point of the arc-shaped convex surface is opposite to the hole wall of the first hole portion. When the first shaft segment contacts the hole wall of the mounting hole, the inflection point of the arc-shaped convex surface contacts the hole wall of the first hole portion.

[0010] In one embodiment, the rotating shaft further includes a second shaft segment connected to one end of the first shaft segment, and a third shaft segment connected to the second shaft segment away from the first shaft segment, wherein the end of the first shaft segment away from the second shaft segment is used to be fixedly connected to the impeller; The housing assembly also has a limiting cavity and a through hole. The limiting cavity communicates with the mounting hole, and the through hole communicates with the limiting cavity. The second shaft segment is rotatably housed in the limiting cavity, and the third shaft segment is rotatably inserted through the through hole. The cross-sectional dimension of the second shaft segment is larger than the diameter of the mounting hole and the diameter of the through hole.

[0011] In one embodiment, the housing assembly further has a receiving cavity communicating with the through hole, and the rotating shaft further has a fourth shaft segment connected to the end of the third shaft segment away from the second shaft segment, the fourth shaft segment being received within the receiving cavity, the fourth shaft segment being thinner than the third shaft segment; the driving device further includes a rotor and a stator received within the receiving cavity, the rotor being fixedly connected to the fourth shaft segment, the stator being capable of driving the rotor to rotate, the rotor being capable of driving the rotating shaft to rotate, and the fourth shaft segment being at least partially received within the stator.

[0012] In one embodiment, the rotor is magnetic, and the stator includes a first stator unit and a second stator unit, both of which are capable of generating a rotating magnetic field that drives the rotor to rotate. The first stator unit, the rotor, and the second stator unit are arranged sequentially along the axis of the fourth shaft segment, which is rotatably disposed through the first stator unit. The rotor is fixed to the end of the fourth shaft segment away from the third shaft segment, and the second stator unit and the rotating shaft are spaced apart along the axis of the fourth shaft segment. Both the first stator unit and the second stator unit have multiple coil windings. The multiple coil windings of the first stator unit are arranged around the fourth shaft segment, and the multiple coil windings of the second stator unit are arranged around the axis of the fourth shaft segment. Both the coil windings of the second stator unit and the coil windings of the first stator unit have magnetic columns. The cross-sectional dimension of the magnetic column of the second stator unit is larger than that of the magnetic column of the first stator unit.

[0013] A blood pump includes an impeller and a drive device as described in any of the preceding claims, wherein the impeller is fixed to the rotating shaft and is rotatable with the rotating shaft.

[0014] Because the drive shaft will wobble during rotation, it will come into contact with the wall of the mounting hole. The larger the contact area between the shaft and the wall of the mounting hole, the greater the wear on the shaft. The first shaft section of the drive shaft has an arc-shaped convex surface in the circumferential direction. At the inflection point of the arc-shaped convex surface, the gap between the arc-shaped convex surface and the wall of the mounting hole is the smallest. This ensures that when the first shaft section contacts the wall of the mounting hole of the housing assembly, the inflection point of the arc-shaped convex surface contacts the wall of the mounting hole in a point-to-surface contact manner, thereby reducing the contact area between the shaft and the wall of the mounting hole and reducing the wear on the shaft. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of the blood pump according to the first embodiment; Figure 2 for Figure 1The blood pump shown omits a partial exploded view of the cannula assembly. Figure 3 for Figure 1 The blood pump shown is a cross-sectional view of the cannula assembly with some parts omitted. Figure 4 for Figure 1 A schematic diagram of the structure of the first bushing of the blood pump shown; Figure 5 for Figure 1 The diagram shows the structure of the second bushing of the blood pump. Figure 6 for Figure 1 A schematic cross-sectional view of the first and second bushings assembled in the blood pump shown. Figure 7 for Figure 1 A schematic diagram of the shaft tube of the blood pump shown; Figure 8 for Figure 1 A cross-sectional view of the blood pump after the first bushing, second bushing, and rotating shaft are assembled. Figure 9 for Figure 8 A schematic diagram of the partial structure at point A; Figure 10 for Figure 1 The diagram shows the structure of the rotor of the blood pump. Figure 11 for Figure 10 The cross-sectional view of the rotor shown; Figure 12 for Figure 10 An exploded view of the rotor shown; Figure 13 This is a partial cross-sectional view of the drive device of the blood pump in the second embodiment; Figure 14 This is a partial schematic diagram of the drive device of the blood pump according to the third embodiment; Figure 15 This is a partial schematic diagram of the drive device of the blood pump according to the fourth embodiment; Figure 16 This is a partial schematic diagram of the drive device for the blood pump in the fifth embodiment. Detailed Implementation

[0016] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0017] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "inner," "outer," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0018] In this paper, "proximal end" is defined as the end closer to the operator, and "distal end" is defined as the end farther from the operator.

[0019] See Figure 1 and Figure 2 The blood pump 1 of the first embodiment of the present invention includes a drive device 20, a cannula assembly 30, an impeller 41, and a catheter 42. The cannula assembly 30 is connected to the distal end of the drive device 20, and the catheter 42 is connected to the proximal end of the drive device 20. The impeller 41 is rotatably disposed within the cannula assembly 30 and is connected to the drive device 20. The drive device 20 can drive the impeller 41 to rotate, thereby realizing the blood pumping function of the blood pump 1.

[0020] Specifically, the cannula assembly 30 has an inlet 301 and an outlet 302. The outlet 302 is closer to the drive unit 20 than the inlet 301. That is, the outlet 302 is located at the proximal end of the cannula assembly 30, and the inlet 301 is located at the distal end of the cannula assembly 30. In one embodiment, the cannula assembly 30 extends through a heart valve, such as an aortic valve, while the inlet 301 is located inside the heart, and the outlet 302 and drive unit 20 are located outside the heart in a blood vessel such as the aorta. When the impeller 41 rotates, blood flows into the cannula assembly 30 from the inlet 301 and then flows out of the cannula assembly 30 from the outlet 302 to enter a blood vessel such as the aorta.

[0021] In some embodiments, the cannula assembly 30 includes an insertion tube 31 and an outlet tube 32, which are fixedly connected. The outlet tube 32 connects the insertion tube 31 and the drive device 20, i.e., the distal end of the outlet tube 32 is connected to the proximal end of the insertion tube 31, and the proximal end of the outlet tube 32 is connected to the drive device 20. An inlet 301 is formed in the insertion tube 31, and an outlet 302 is formed in the outlet tube 32. An impeller 41 is housed in the outlet tube 32; the position of the impeller 41 approximately corresponds to the position of the outlet 302.

[0022] The conduit 42 is connected to the end of the drive unit 20 that is away from the sleeve assembly 30. The conduit 42 is used to accommodate various supply lines, such as cleaning lines for introducing cleaning fluid into the drive unit 20, wires for supplying power to the drive unit 20, and support components for supporting the conduit 42.

[0023] Please combine them together Figure 3 In some embodiments, the drive device 20 includes a housing assembly 100, a rotating shaft 200, a stator 330, and a rotor 340. The housing assembly 100 has a mounting hole 131 through which the rotating shaft 200 is rotatably inserted; an impeller 41 is fixedly connected to the rotating shaft 200; both the stator 330 and the rotor 340 are housed within the housing assembly 100; the rotor 340 is fixedly connected to the rotating shaft 200; the stator 330 can drive the rotor 340 to rotate, and the rotor 340 can drive the rotating shaft 200 to rotate; the impeller 41 can rotate with the rotating shaft 200 to achieve the blood pumping function of the blood pump 1. A wire in the conduit 42 extends into the housing assembly 100 and is electrically connected to the stator 330 to supply power to the stator 330.

[0024] In the illustrated embodiment, the housing assembly 100 includes a pump housing 110, a shaft tube 120, a first bushing 130, and a second bushing 140. The pump housing 110, shaft tube 120, first bushing 130, and second bushing 140 are separate components before assembly; that is, the housing assembly 100 is assembled from the separate pump housing 110, shaft tube 120, first bushing 130, and second bushing 140.

[0025] The pump casing 110 is a cylindrical structure with a roughly circular cross-section. The pump casing 110 has a receiving cavity 112, in which the stator 330 and the rotor 340 are both housed.

[0026] One end of the shaft tube 120 is fixedly connected to the pump housing 110, and the other end is fixedly connected to the sleeve assembly 30 (specifically the outlet pipe 32). The shaft tube 120 has a mounting port 121, which is located at the end of the shaft tube 120 near the sleeve assembly 30.

[0027] The first bushing 130 and the second bushing 140 are fixedly housed within the shaft tube 120. Both the first bushing 130 and the second bushing 140 are fixedly connected to the shaft tube 120. The first bushing 130 and the second bushing 140 are arranged axially along the shaft tube 120, with the first bushing 130 positioned closer to the impeller 41 than the second bushing 140. A mounting hole 131 is formed in the first bushing 130. The rotating shaft 200 is rotatably inserted through the first bushing 130 and the second bushing 140. Specifically, the first bushing 130 and the second bushing 140 are separate units; both the first bushing 130 and the second bushing 140 can be inserted into the mounting port 121 of the shaft tube 120, meaning the maximum outer diameter of both the first bushing 130 and the second bushing 140 is slightly smaller than the diameter of the mounting port 121.

[0028] Specifically, a bearing protrusion 122 is provided at one end of the shaft tube 120 near the pump housing 110, and the second shaft sleeve 140 abuts against the bearing protrusion 122; the first shaft sleeve 130 abuts against the second shaft sleeve 140, so that the bearing protrusion 122 limits the first shaft sleeve 130 and the second shaft sleeve 140 in the axial direction of the pump housing 110, so as to facilitate the assembly of the first shaft sleeve 130 and the second shaft sleeve 140. In one embodiment, the bearing protrusion 122 is approximately annular. The shaft tube 120 is also provided with an adhesive injection hole 123, which is filled with adhesive. The adhesive fixes the first shaft sleeve 130 and the second shaft sleeve 140 to the shaft tube 120 and secures the first shaft sleeve 130 and the second shaft sleeve 140 together.

[0029] See Figure 3 , Figure 4 , Figure 5 and Figure 6 The first bushing 130 has a limiting hole 132, the diameter of which is larger than the diameter of the mounting hole 131. The mounting hole 131 is closer to the impeller 41 than the limiting hole 132. The limiting hole 132 and the mounting hole 131 are coaxially arranged and interconnected, forming a stepped hole together. The first bushing 130 has a first limiting surface 133, which defines a portion of the boundary of the limiting hole 132. The first limiting surface 133 can be perpendicular to the axial direction of the rotating shaft 200 or inclined relative to the axial direction of the rotating shaft 200.

[0030] The second bushing 140 includes a thick section 141 and a thin section 142. The cross-sectional dimension of the thin section 142 is smaller than that of the thick section 141. The thick section 141 has an abutment surface 1411. In the illustrated embodiment, the outer contours of both the thin section 142 and the thick section 141 are circular. Therefore, the smaller cross-sectional dimension of the thin section 142 means that the outer diameter of the thin section 142 is smaller than that of the thick section 141. The thin section 142 protrudes from the abutment surface 1411. The second bushing 140 has a through hole 143, which extends from the end face of the thin section 142 away from the abutment surface 1411 to the side of the thick section 141 away from the abutment surface 1411, so that the through hole 143 passes through both the thick section 141 and the thin section 142. The diameter of the limiting hole 132 is larger than the diameter of the through hole 143. The thin segment 142 is received in the limiting hole 132, and the abutting surface 1411 abuts against the first bushing 130. The limiting effect of the abutting surface 1411 and the guiding effect of the thin segment 142 improve installation accuracy and efficiency. The side of the thick segment 141 away from the abutting surface 1411 abuts against the bearing protrusion 122. The end face of the thin segment 142 away from the abutting surface 1411 is the second limiting surface 144, which is spaced apart from and opposite to the first limiting surface 133, such that the first limiting surface 133 and the second limiting surface 144 are spaced apart along the axial direction of the rotating shaft 200. The second limiting surface 144 can be perpendicular to the axial direction of the rotating shaft 200 or inclined relative to the axial direction of the rotating shaft 200. In the illustrated embodiment, both the first limiting surface 133 and the second limiting surface 144 are perpendicular to the axial direction of the rotating shaft 200, and the first limiting surface 133 and the second limiting surface 144 are parallel and opposite.

[0031] The limiting hole 132, its wall 132a, the first limiting surface 133, and the second limiting surface 144 together form a limiting cavity 150. Both the mounting hole 131 and the through hole 143 communicate with this limiting cavity 150. In other words, the limiting cavity 150 is actually a part of the limiting hole 132, and the first limiting surface 133 and the second limiting surface 144 are the two cavity wall surfaces of the limiting cavity 150 along the axial direction of the rotating shaft 200.

[0032] A rotating shaft 200 passes through the mounting hole 131, the limiting cavity 150, and the through hole 143. One end of the rotating shaft 200 is housed in the pump casing 110, and the other end extends into the sleeve assembly 30 and is fixedly connected to the impeller 41. Gap spaces for the flow of cleaning fluid are provided between the rotating shaft 200 and the wall of the mounting hole 131, between the rotating shaft 200 and the wall of the limiting cavity 150, and between the rotating shaft 200 and the wall of the through hole 143. The cleaning fluid can flow from the pump casing 110 through the gaps between the rotating shaft 200 and the wall of the through hole 143, between the rotating shaft 200 and the wall of the limiting cavity 150, and between the rotating shaft 200 and the mounting hole 131 to enter the sleeve assembly 30 and exit from the outlet 302. Figure 8The dashed arrow in the middle represents the flow direction of the cleaning fluid. The flow direction of the cleaning fluid is opposite to the flow direction of blood in the sleeve assembly 30. This can prevent blood in the sleeve assembly 30 from entering the drive device 20 through the mounting hole 131. In addition, the cleaning fluid also plays a lubricating role. The cleaning fluid can reduce the frictional resistance between the rotating shaft 200 and the first bushing 130 and the second bushing 140, and reduce the wear between the rotating shaft 200 and the first bushing 130 and the second bushing 140.

[0033] It should be noted that the housing assembly 100 is not limited to the above-described manner. In some embodiments, two or more of the pump housing 110, shaft tube 120, first bushing 130, and second bushing 140 may be integral structures. For example, the pump housing 110 and shaft tube 120 may be integrally formed. For example, one of the first bushing 130 and the second bushing 140 may be integrally formed with the shaft tube 120. For example, the first bushing 130 may be a disc-shaped ring structure. For example, the first bushing 130 may be composed of two separate tubular rings and a disc-shaped ring. For example, the second bushing 140 may only have a thick section 141.

[0034] Please refer to the following: Figure 3 , Figure 7 , Figure 8 and Figure 9 In some embodiments, the rotating shaft 200 includes a first shaft segment 210, a second shaft segment 220, a third shaft segment 230, and a fourth shaft segment 240 connected in sequence. The axes of the first shaft segment 210, second shaft segment 220, third shaft segment 230, and fourth shaft segment 240 coincide. The first shaft segment 210 is rotatably disposed through the mounting hole 131 and is fixedly connected to the impeller 41. The second shaft segment 220 is rotatably received in the limiting cavity 150. The third shaft segment 230 is rotatably disposed through the through hole 143; the fourth shaft segment 240 is received in the receiving cavity 112 of the pump casing 110. The fourth shaft segment 240 is fixedly connected to the rotor 340.

[0035] A portion of the first shaft segment 210 is housed within the housing assembly 100, and a portion extends into the sleeve assembly 30 and is fixedly connected to the impeller 41. The first shaft segment 210 has a circumferentially convex arcuate surface 211. Specifically, the arcuate arcuate surface 211 protrudes radially away from the axis of the first shaft segment 210 (radial is the direction perpendicular to the axis of the first shaft segment 210). At least a portion of the arcuate arcuate surface 211 is located within the mounting hole 131, with the inflection point of the arcuate arcuate surface 211 facing the wall of the mounting hole 131; and the gap between the arcuate arcuate surface 211 and the wall of the mounting hole 131 is minimal at the inflection point of the arcuate arcuate surface 211. When the first shaft segment 210 contacts the wall of the mounting hole 131, the inflection point of the arcuate arcuate surface 211 contacts the wall of the mounting hole 131. Because the rotating shaft 200 will have a certain radial wobble during rotation, the first shaft segment 210 will contact the wall of the mounting hole 131 when the rotating shaft 200 wobbles. The larger the contact area between the first shaft segment 210 and the wall of the mounting hole 131, the greater the wear of the first shaft segment 210. The aforementioned rotating shaft 200 reduces the contact area between the first shaft segment 210 and the wall of the mounting hole 131 by setting an arc-shaped convex surface 211 in the circumferential direction of the first shaft segment 210, so that when the first shaft segment 210 contacts the wall of the mounting hole 131, only the inflection point of the arc-shaped convex surface 211 contacts the wall of the mounting hole 131, forming a point-to-surface contact, thereby reducing the wear of the rotating shaft 200.

[0036] It should be noted that the inflection point of the arc-shaped convex surface 211 in this application refers to the point where the distance between the arc-shaped convex surface 211 and the axis OO' of the first shaft segment 210 is the largest, that is, the most convex point of the arc-shaped convex surface 211. For example, in the illustrated embodiment, the inflection point of the arc-shaped convex surface 211 is the line PP'. Since the axes of the first shaft segment 210, the second shaft segment 220, the third shaft segment 230, and the fourth shaft segment 240 coincide, the axis OO' of the first shaft segment 210 is the axis of the rotating shaft 200, and also the axis of the second shaft segment 220, the third shaft segment 230, and the fourth shaft segment 240.

[0037] Specifically, the arc-shaped convex surface 211 is arranged around the axis OO' of the first shaft segment 210 for one full turn. This arrangement of the arc-shaped convex surface 211 facilitates the manufacturing of the rotating shaft 200. In the illustrated embodiment, the arc-shaped convex surface 211 is continuously arranged around the axis of the first shaft segment 210 for one full turn. It can be understood that in other embodiments, multiple spaced arc-shaped convex surfaces 211 can also be arranged along the axial direction of the first shaft segment 210.

[0038] In some embodiments, the width of the gap between the inflection point (line PP′) of the arcuate convex surface 211 and the wall of the mounting hole 131 is less than or equal to 2 μm. Since the smallest red blood cells (approximately 8 μm in diameter and approximately 2 μm in thickness) have difficulty entering a gap with a width less than or equal to 2 μm, and the backwashing cleaning fluid passes through this gap, blood is prevented from entering this gap.

[0039] Specifically, the distance H is defined as the distance from the inflection point (line PP′) of the arcuate convex surface 211 along the axial direction of the first shaft segment 210 to the plane containing the opening of the mounting hole 131 near the impeller 41. The value of H is in the range of H≤0.2mm. In the illustrated embodiment, the plane containing the opening of the mounting hole 131 near the impeller 41 is perpendicular to the axial direction of the first shaft segment 210, or in other words, perpendicular to the axis OO' of the first shaft segment 210. Furthermore, with a thickness of 0.1mm ≤ H ≤ 0.2mm, the inflection point (line PP′) of the arc-shaped convex surface 211 is located inside the mounting hole 131 and slightly lower than the opening of the mounting hole 131 near the impeller 41. This ensures that the wall of the mounting hole 131 provides better support for the rotating shaft 200, so that when the rotating shaft 200 contacts the wall of the mounting hole 131, only the inflection point (line PP′) of the arc-shaped convex surface 211 contacts the wall of the mounting hole 131. On the other hand, it ensures the flushing force of the cleaning fluid.

[0040] Specifically, the arcuate convex surface 211 has a first arcuate portion 212 and a second arcuate portion 213 connected to the first arcuate portion 212. The first arcuate portion 212 and the second arcuate portion 213 are arranged along the axial direction of the first shaft segment 210. The connection point between the first arcuate portion 212 and the second arcuate portion 213 is the inflection point (line PP′) of the arcuate convex surface 211. Along the axial direction of the first shaft segment 210 and towards the impeller 41, the distance from the first arcuate portion 212 to the axis OO′ of the first shaft segment 210 gradually increases, and the distance from the second arcuate portion 213 to the axis OO′ of the first shaft segment 210 gradually decreases. In the illustrated embodiment, the entire arcuate convex surface 211 is located within the mounting hole 131; along the axis OO' of the first shaft segment 210 and towards the impeller 41, the width of the gap between the first arcuate surface 212 and the wall of the mounting hole 131 gradually decreases, and the width of the gap between the second arcuate surface 213 and the wall of the mounting hole 131 gradually increases. At the connection between the first arcuate surface 212 and the second arcuate surface 213, i.e., at line PP', the width of the gap between the arcuate convex surface 211 and the wall of the mounting hole 131 is the smallest.

[0041] In some embodiments, in order to prevent red blood cells from entering between the first shaft segment 210 and the wall of the mounting hole 131, the width of the gap between the wall of the mounting hole 131 at the opening near the impeller 41 and the first shaft segment 210 is less than or equal to 2 μm. Then, the width of the gap between the inflection point (line PP′) of the arcuate convex surface 211 and the wall of the mounting hole 131 is less than 2 μm, that is, smaller than the width of the gap between the wall of the mounting hole 131 at the opening near the impeller 41 and the first shaft segment 210.

[0042] It is understandable that the width of the gap between the inflection point of the arc-shaped convex surface 211 and the wall of the mounting hole 131, as well as the width of the gap between the wall of the mounting hole 131 at the opening near the impeller 41 and the first shaft section 210, can be adjusted according to needs and design.

[0043] To facilitate the entry of cleaning fluid from the limiting cavity 150 into the mounting hole 131, the mounting hole 131 has a first hole portion 131a and a second hole portion 131b that are connected. The diameter of the first hole portion 131a is constant, and the diameter of the second hole portion 131b gradually decreases along the direction close to the first hole portion 131a. The first shaft segment 210 passes through the first hole portion 131a and the second hole portion 131b. The inflection point (line PP′) of the arc-shaped convex surface 211 is opposite to the hole wall of the first hole portion 131a. When the first shaft segment 210 contacts the hole wall of the mounting hole 131, the inflection point (line PP′) of the arc-shaped convex surface 211 contacts the hole wall of the first hole portion 131a. That is, the diameter of the end of the second hole 131b near the limiting cavity 150 is larger than the diameter of the first hole 131a. The first hole 131a with a constant diameter can better support the rotating shaft 200 and reduce the swaying arc of the rotating shaft 200. The second hole 131b with a diameter that changes in the above manner can guide the cleaning fluid so that the cleaning fluid can enter the mounting hole 131.

[0044] In some embodiments, the wall of the through hole 143 near the limiting cavity 150 is formed with an inner chamfer, which helps to reduce the contact area between the rotating shaft 200 and the second bushing 140 and reduce the wear of the rotating shaft 200.

[0045] The second shaft segment 220 is fixedly connected to the end of the first shaft segment 210 away from the impeller 41. The second shaft segment 220 is rotatably housed in the limiting cavity 150; in other words, the cross-sectional dimension of the second shaft segment 220 is smaller than the cross-sectional dimension of the limiting cavity 150. The diameter of the cross-section of the second shaft segment 220 is larger than the diameter of the mounting hole 131 and the diameter of the through hole 143, so that the second shaft segment 220 is confined in the limiting cavity 150. Thus, the second shaft segment 220 will not enter the through hole 143 and the mounting hole 131. The second shaft segment 220 is located between the first limiting surface 133 and the second limiting surface 144, thereby limiting the rotating shaft 200 axially.

[0046] Specifically, the second shaft segment 220 can abut against the first limiting surface 133 and the second limiting surface 144 to prevent the rotating shaft 200 from axially moving or to limit its axial movement distance. In some embodiments, the second shaft segment 220 is always in sliding contact with the first limiting surface 133 and the second limiting surface 144; in other embodiments, the distance between the first limiting surface 133 and the second limiting surface 144 is slightly larger than the axial length of the second shaft segment 220, so that during the rotation of the rotating shaft 200, the second shaft segment 220 has a certain floating space between the first limiting surface 133 and the second limiting surface 144 for the flow of cleaning fluid. A flow gap 151 for the flow of cleaning fluid is formed between the second shaft segment 220 and the cavity wall of the limiting cavity 150 extending along the axis OO'.

[0047] Please refer to it again. Figure 4 , Figure 5 and Figure 6 Furthermore, a first guide groove 1331 is formed in a partial recess of the first limiting surface 133. The first guide groove 1331 extends from the wall 1311 of the mounting hole 131 to the wall 132a of the limiting hole 132, thereby connecting the mounting hole 131 and the limiting hole 132. Since the limiting cavity 150 is part of the limiting hole 132, the first guide groove 1331 also connects to the limiting cavity 150. A second guide groove 1441 is formed in a partial recess of the second limiting surface 144. The second guide groove 1441 extends from the wall 1311 of the through hole 143 to the outer peripheral surface of the thin segment 142, and connects the through hole 143 and the limiting cavity 150. Since the flow gap 151 is actually part of the limiting cavity 150, the flow gap 151 simultaneously connects the first guide groove 1331 and the second guide groove 1441. The first guide channel 1331 and the second guide channel 1441 are designed to facilitate the flow of cleaning fluid.

[0048] It should be noted that in some embodiments, only one of the first guide channel 1331 and the second guide channel 1441 may be provided, or neither the first guide channel 1331 nor the second guide channel 1441 may be provided.

[0049] In some embodiments, the two ends of the second shaft segment 220 in the axial direction are provided with chamfers 222. This reduces the contact area between the rotating shaft 200 and the first limiting surface 133 and / or the second limiting surface 144, and further reduces the contact area between the rotating shaft 200 and the first bushing 130 and the second bushing 140, thereby further reducing the wear of the rotating shaft 200. On the other hand, it prevents the sharp edges of the second shaft segment 220 in contact with the first bushing 130 and the second bushing 140 from causing wear to the first bushing 130 and the second bushing 140, and can also form a guiding effect on the cleaning fluid.

[0050] The third shaft segment 230 is rotatably inserted through the through hole 143. There is a gap between the third shaft segment 230 and the wall of the through hole 143 for the flow of cleaning fluid.

[0051] The fourth shaft segment 240 is connected to the end of the third shaft segment 230 away from the second shaft segment 220, and the fourth shaft segment 240 is received within the receiving cavity 112. The cross-sectional dimension of the fourth shaft segment 240 is smaller than that of the third shaft segment 230. The rotor 340 is fixedly connected to the fourth shaft segment 240. The fourth shaft segment 240 is at least partially received within the stator 330.

[0052] Specifically, the rotating shaft 200, the first bushing 130, and the second bushing 140 can be made of ceramic material, which can improve the wear resistance of the rotating shaft 200, the first bushing 130, and the second bushing 140, and further prevent wear on the rotating shaft 200, the first bushing 130, and the second bushing 140.

[0053] Please combine again Figure 3 The stator 330 includes a first stator unit 332 and a second stator unit 333, both of which can drive the rotor 340 to rotate. Specifically, the first stator unit 332 and the second stator unit 333 are spaced apart along the extension direction of the shaft 200. Both the first stator unit 332 and the second stator unit 333 are fixedly connected to the housing assembly 100. The fourth shaft segment 240 of the shaft 200 is rotatably inserted through the first stator unit 332. That is, the rotor 340 is rotatable relative to the housing assembly 100, while the first stator unit 332 and the second stator unit 333 are not rotatable relative to the housing assembly 100.

[0054] The first stator unit 332 and the second stator unit 333 can be connected in parallel or in series. In some embodiments, the first stator unit 332 and the second stator unit 333 can synchronously drive the rotor 340 to rotate. The first stator unit 332 and the second stator unit 333 can drive the rotor 340 to rotate together, or they can drive the rotor 340 to rotate individually.

[0055] In some embodiments, the rotor 340 is magnetic, and the stator 330 is capable of generating a rotating magnetic field that drives the rotor 340 to rotate. Specifically, both the first stator unit 332 and the second stator unit 333 are capable of generating a rotating magnetic field that drives the rotor 340 to rotate.

[0056] Specifically, the first stator unit 332 includes a first magnetic core 3321, a first coil 3322, and a first back plate 3323. The first back plate 3323 is fixed to the housing assembly 100; in the illustrated embodiment, the first back plate 3323 is fixed to the shaft tube 120. Multiple first magnetic cores 3321 are arranged at circumferential intervals. Specifically, the extending direction of each first magnetic core 3321 is consistent with the extending direction of the rotating shaft 200. Each first magnetic core 3321 is fixed to the first back plate 3323. The first coil 3322 is wound around the first magnetic core 3321. One first coil 3322 and one first magnetic core 3321 constitute a coil winding. Thus, the multiple coil windings of the first stator unit 332 are arranged around the fourth shaft segment 240.

[0057] The structure of the second stator unit 333 is similar to that of the first stator unit 332. The second stator unit 333 includes a second magnetic core 3331, a second coil 3332, and a second back plate 3333. The second back plate 3333 is fixed to the housing assembly 100. Multiple second magnetic cores 3331 are arranged at circumferential intervals. Specifically, the extension direction of each second magnetic core 3331 is parallel to the axis of the fourth shaft segment 240 (i.e., axis OO'). Each second magnetic core 3331 is fixed to the second back plate 3333. The second coil 3332 is wound around the second magnetic core 3331. One second coil 3332 and one second magnetic core 3331 constitute a coil winding. Therefore, the multiple coil windings of the second stator unit 333 are arranged around the axis of the fourth shaft segment 240 (i.e., OO').

[0058] In some embodiments, both the first magnetic core 3321 and the second magnetic core 3331 include a magnetic post and a head (i.e., a pole shoe) disposed at one end of the magnetic post, with the extension direction of the magnetic post aligned with the extension direction of the rotating shaft. A first back plate 3323 engages with the end of the magnetic post of the first magnetic core 3321 furthest from the head; a second back plate 3333 engages with the end of the magnetic post of the second magnetic core 3331 furthest from the head. The magnetic post is generally a uniformly sized column in its extension direction, meaning the cross-sectional dimensions of the magnetic post 3331 remain constant; in simpler terms, the magnetic post 3331 is of uniform thickness. A first coil 3322 is wound around the magnetic post of the first magnetic core 3321, and a second coil 3332 is wound around the magnetic post of the second magnetic core 3331.

[0059] Please combine Figure 3In the illustrated embodiment, both the first magnetic core 3321 and the second magnetic core 3331 consist only of magnetic pillars, meaning neither has a head (i.e., a pole shoe) with a large cross-sectional width. Therefore, the magnetic pillars of the first stator unit 332 are the first magnetic core 3321, and the magnetic pillars of the second stator unit 333 are the second magnetic core 3331. In this case, the entire first magnetic core 3321 and the entire second magnetic core 3331 can be magnetically coupled to the rotor 340. Compared to a magnetic core with pole shoes, a magnetic core with only magnetic pillars can reduce magnetic losses and increase the magnetic coupling density between the core and the rotor 340, thereby increasing the torque of the stator unit on the rotor 340 under the same current. Furthermore, the absence of a head in the magnetic core can significantly reduce the power reduction of the drive device 20 caused by localized magnetic short circuits due to contact between adjacent magnetic cores.

[0060] It is understood that the first magnetic core 3321 and the second magnetic core 3331 are not limited to the two methods mentioned above. In some embodiments, one of the first magnetic core 3321 and the second magnetic core 3331 may have both a magnetic post and a head, while the other may only have a magnetic post.

[0061] In some embodiments, the cross-sectional shape of the magnetic pillars of the first magnetic core 3321 and the second magnetic core 3331 is approximately triangular prism, with one edge of each magnetic pillar facing the axis of rotation. In some embodiments, the edges of the magnetic pillars are rounded, i.e., the edges of the magnetic pillars are relatively smooth and blunt rounded edges, thereby eliminating sharp corners on the magnetic pillars. This not only facilitates the subsequent winding of the coil but also helps protect the insulating material covering the coil. In other embodiments, the cross-sectional shape of the magnetic pillars of the first magnetic core 3321 and the second magnetic core 3331 can also be fan-shaped, circular, trapezoidal, fan-ring-shaped, etc.

[0062] In the illustrated embodiment, along the axis of the fourth shaft segment 240 (i.e., along axis OO'), the rotating shaft 200 is spaced apart from the second stator unit 333. Specifically, the end of the fourth shaft segment 240 furthest from the third shaft segment 230 is spaced apart from the second stator unit 333; that is, the fourth shaft segment 240 of the rotating shaft 200 does not penetrate into the second stator unit 333. The cross-sectional dimension of the magnetic post of the second stator unit 333 is larger than the cross-sectional dimension of the magnetic post of the first stator unit 332.

[0063] The larger the cross-sectional area of ​​the magnetic column, the greater the magnetic flux generated, the greater the torque of the stator unit on the rotor 340, and the smaller the required current, which helps to reduce power consumption and heat generation. With the first stator unit 332 and the second stator unit 333 having the same cross-sectional dimensions and the outer diameter of the housing assembly 100 remaining unchanged, and given that the shaft 200 is located outside the second stator unit 333 and does not pass through it, the cross-sectional size of the magnetic column of the second stator unit 333 can be reasonably increased without increasing the outer diameter of the pump housing 110. This increases the driving torque of the second stator unit 333 on the rotor 340. With the same required torque, this method can reasonably reduce the current supply to the stator 330, thereby reducing power consumption and also reducing the heat generated by the drive device 20, preventing the blood pump 1 from overheating during operation and causing discomfort or even harm to the human body.

[0064] It should be noted that in other embodiments, the rotating shaft 200 can also be inserted into the second stator unit 333. In this case, the cross-sectional dimensions of the magnetic columns of the first stator unit 332 and the second stator unit 333 are the same.

[0065] The first backplate 3323 and the second backplate 3333 are generally flat plate structures. The first backplate 3323 and the second backplate 3333 are made of the same material as the first magnetic core 3321 and the second magnetic core 3331, such as soft magnetic materials like cobalt steel.

[0066] The backplate functions to close the magnetic circuit of the stator unit, thereby promoting and increasing the generation of magnetic flux in the stator unit and improving the coupling capability between each stator unit and the rotor 340. In other words, the first backplate 3323 in the first stator unit 332 promotes and increases the generation of magnetic flux in the first stator unit 332, improving the coupling capability between the first stator unit 332 and the rotor 340; similarly, the second backplate 3333 in the second stator unit 333 promotes and increases the generation of magnetic flux in the second stator unit 333, improving the coupling capability between the second stator unit 333 and the rotor 340. Since the backplate increases magnetic flux, providing backplates in both the first stator unit 332 and the second stator unit 333 also helps to reduce the overall diameter of the drive device 20.

[0067] Specifically, the drive device 20 also includes a positioning member 360, which is fixedly connected inside the pump housing 110. The positioning member 360 has a positioning post 364, and the second back plate 3333 of the second stator unit 333 has a positioning hole 3334, through which the positioning post 364 passes. This allows the positioning member 360 to perform its positioning function for the second stator unit 333, improving the installation accuracy and efficiency of the second stator unit 333. Specifically, the central axis of the positioning post 364 coincides with the central axis of the second stator unit 333. In some embodiments, the positioning member 360 also has a through hole 365, which can be used to connect with a cleaning pipeline that supplies cleaning fluid into the drive device 20 or to install a cleaning pipeline.

[0068] It should be noted that in some embodiments, the first stator unit 332 may not have a first back plate 3323, and the second stator unit 333 may not have a second back plate 3333. Alternatively, one of the first stator unit 332 and the second stator unit 333 may have a back plate, while the other may not. If the second stator unit 333 does not have a second back plate 3333, multiple positioning holes can be directly formed on the positioning member 360, and one end of each of the multiple second magnetic cores 3331 can be positioned in one of the multiple positioning holes.

[0069] In some embodiments, the positioning member 360 may be omitted. In this case, a locking position for engaging with the edge of the second back plate 3333 may be provided in the pump housing 110, so that the second stator unit 333 is fixed by engaging with the second back plate 3333; or the second stator unit 333 may be fixed by bonding it to the pump housing 110 with an adhesive. The first stator unit 332 may be fixed by bonding it to the shaft tube 120 with an adhesive, or it may be fixed by engaging with the first back plate 3323 with a corresponding locking position provided in the pump housing 110.

[0070] Please combine them together Figure 3 and Figures 10-12The rotor 340 is housed in the receiving cavity 112 of the pump casing 110. In the illustrated embodiment, along the axis OO', the rotor 340 is located between the first stator unit 333 and the second stator unit 334. Specifically, the rotor 340 includes a first magnet 342 and a second magnet 343, both of which are fixed to the fourth shaft segment 240. The first magnet 342 and the second magnet 343 are both located between the first stator unit 332 and the second stator unit 333, that is, along the axis OO', the first stator unit 332, the first magnet 342, the second magnet 343, and the second stator unit 333 are arranged sequentially. The first stator unit 332 can generate a rotating magnetic field that drives the first magnet 342 to rotate, and the second stator unit 333 can generate a rotating magnetic field that drives the second magnet 343 to rotate. The two stator units provide torque to the rotor 340 through their respective magnets, which increases the driving force for the rotation of the rotor 340.

[0071] Specifically, the rotor 340 also includes a flywheel 344, which is fixedly connected to the fourth shaft segment 240 of the rotating shaft 200. The flywheel 344 is located between the first stator unit 332 and the second stator unit 333, and both the first magnet 342 and the second magnet 343 are fixedly connected to the flywheel 344. More specifically, the flywheel 344 is fixedly connected to the end of the fourth shaft segment 240 away from the third shaft segment 230.

[0072] By setting the flywheel 344, the connection strength between the first magnet 342 and the second magnet 343 and the fourth shaft segment 240 can be enhanced. In addition, by setting both the first magnet 342 and the second magnet 343 on the same flywheel 344, the shaking of the fourth shaft segment 240 during rotation can be reduced, making the fourth shaft segment 240 more stable during rotation.

[0073] In the illustrated embodiment, the flywheel 344 includes an inner tube 3442, a disc-shaped portion 3444, and an outer ring wall 3446. Both the inner tube 3442 and the outer ring wall 3446 are cylindrical structures, while the disc-shaped portion 3444 is an annular disc structure. Both the inner tube 3442 and the outer ring wall 3446 are fixedly connected to the disc-shaped portion 3444. The outer ring wall 3446 surrounds the disc-shaped portion 3444, and the inner tube 3442 and the outer ring wall 3446 are coaxially arranged. A fourth shaft segment 240 passes through the inner tube 3442 and is fixedly connected to it. An accommodating space is formed between the inner tube 3442 and the outer ring wall 3446, and the disc-shaped portion 3444 divides this accommodating space into two mounting cavities 3448. Both mounting cavities 3448 are annular cavities. The first magnet 342 and the second magnet 343 are respectively housed in the two mounting cavities 3448. Both the first magnet 342 and the second magnet 343 are annular, and the shapes of the two mounting cavities 3448 are adapted to the first magnet 342 and the second magnet 343, respectively, to facilitate the installation and positioning of the first magnet 342 and the second magnet 343. This arrangement allows the flywheel 344 to limit the movement of the first magnet 342 and the second magnet 343, which not only facilitates the installation of the first magnet 342 and the second magnet 343, but also makes the connection between the first magnet 342 and the second magnet 343 and the flywheel 344 more stable.

[0074] It should be noted that the flywheel 344 is not limited to the structure described above. In some embodiments, the flywheel 344 does not have an outer ring wall 3446; in some embodiments, the flywheel 344 does not have an outer ring wall 3446 and an inner tube 3442. In this case, the fourth shaft segment 240 is fixedly inserted through the disc-shaped portion 3444, for example, at the center of the disc-shaped portion 3444. Compared to a flywheel 344 that only has a disc-shaped portion 3444, providing an inner tube 3442 allows for a more stable connection between the flywheel 344 and the fourth shaft segment 240.

[0075] In some embodiments, the first magnet 342 and the second magnet 343 are both ring-shaped Heilbeck array magnets. Specifically, both the first magnet 342 and the second magnet 343 include multiple magnetic bodies, for example, four, six, eight, or ten magnetic bodies, each magnetic body is fan-shaped, and the multiple magnetic bodies of the first magnet are arranged around the fourth shaft segment 240 to form a ring structure, and the multiple magnetic bodies of the second magnet 343 are arranged around the rotor 340 to form a ring structure.

[0076] More specifically, the first magnet 342 has a first magnetic body 3422 magnetized along the axial direction of the first magnet 342, and the second magnet 343 has a second magnetic body 3432 magnetized along the axial direction of the second magnet 343. The first magnetic body 3422 and the second magnetic body 3432 are respectively disposed on opposite sides of the disc-shaped portion 3444, and the positions of the first magnetic body 3422 and the second magnetic body 3432 correspond to each other. In the extending direction of the rotor 340, the polarities of the first magnetic body 3422 and the second magnetic body 3432 facing the disc-shaped portion 3444 are opposite. This arrangement facilitates the installation of the first magnet 342 and the second magnet 343, avoiding the problem of assembly difficulties caused by the mutual repulsion between the first magnetic body 3422 and the second magnetic body 3432 located in the disc-shaped portion 3444. For example, if the polarity of the first magnetic body 3422 facing the disk-shaped portion 3444 is N pole, then the polarity of the second magnetic body 3432 facing the disk-shaped portion 3444 is S pole. Based on the principle that N poles and S poles attract each other, the interference of magnetic repulsion is eliminated, thereby improving the installation efficiency of the first magnet 342 and the second magnet 343.

[0077] To facilitate the installation of the first magnet 342 and the second magnet 343 and improve their installation accuracy, the flywheel 344 is further provided with a marking portion 345 for determining the installation positions of the first magnet 3422 and the second magnet 3432. The marking portion 345 can be a groove, a scale line, or a marker. When installing the first magnet 342 and the second magnet 343, by marking the position of one of the magnets using the marking portion 345, the installation positions of the remaining magnets can be determined, thus facilitating the installation of the first magnet 342 and the second magnet 343. Specifically, the marking portion 345 is provided on at least one of the inner tube 3442, the disc-shaped portion 3444, and the outer ring wall 3446. Specifically, in the illustrated embodiment, the marking portion 345 is provided on the end faces of both ends of the inner tube 3442.

[0078] The aforementioned drive device and blood pump have at least the following advantages: (1) Since the rotating shaft 200 will have a certain radial wobble during rotation, when the rotating shaft 200 wobbles, the rotating shaft 200 will contact the hole wall of the mounting hole 131. The larger the contact area between the rotating shaft 200 and the hole wall of the mounting hole 131, the greater the wear of the rotating shaft 200. The first shaft segment 210 of the rotating shaft 200 of the above-mentioned drive device 20 is provided with an arc-shaped convex surface 211 in the circumferential direction. At the inflection point PP' of the arc-shaped convex surface 211, the gap between the arc-shaped convex surface 211 and the hole wall of the mounting hole 131 is the smallest. This makes it possible for the first shaft segment 210 to contact the hole wall of the mounting hole 131 of the housing assembly 100 when the arc-shaped convex surface 211 contacts the hole wall of the mounting hole 131, so as to form a point-to-surface contact, thereby reducing the contact area between the first shaft segment 210 and the hole wall of the mounting hole 131 and reducing the wear of the rotating shaft 200.

[0079] (2) The split housing assembly 100 with the above structure, namely the split pump housing 110, shaft tube 120, first shaft sleeve 130 and second shaft sleeve 140 are assembled into housing assembly 100, and the maximum outer diameter of the mounting port 121 of the shaft tube 120 is slightly smaller than the diameter of the mounting hole 121, which can facilitate the assembly of the drive device 20. For example, the first shaft sleeve 130, the second shaft sleeve 140 and the rotating shaft 200 can be assembled in one direction, which can simplify the assembly of the drive device 20 and improve production efficiency.

[0080] (3) Given that the fourth shaft segment 240 of the rotating shaft 200 passes through the stator 330, and the cross-sectional dimension of the fourth shaft segment 240 is smaller than that of the third shaft segment 230, the space occupied by the fourth shaft segment 240 in the radial direction of the stator 330 can be reduced while ensuring the structural strength of the entire rotating shaft 200. While ensuring that the outer diameter of the stator 330 and the pump housing 110 remains unchanged, the cross-sectional dimension of the magnetic column inside the stator 330 can be reasonably increased. In layman's terms, the magnetic column can be reasonably thickened. The larger the cross-sectional dimension of the magnetic column, the greater the magnetic flux generated, the greater the torque of the stator 330 on the rotor 340, and the smaller the required current. This is beneficial to reduce power consumption, reduce heat generation, and prevent the blood pump 1 from overheating due to heat accumulation during operation, which could cause discomfort or even harm to the human body. The larger cross-sectional dimension of the third shaft segment 230 allows the rotating shaft 200 to have greater structural strength at the through hole 143.

[0081] (4) The shaft 200 of the drive device 20 is axially spaced from the second stator unit 333. The cross-sectional size of the magnetic column of the second stator unit 333 can be reasonably increased without increasing the outer diameter of the pump housing 110. This can increase the driving torque of the second stator unit 333 on the rotor 340. Under the same torque requirement, this method can reasonably reduce the current supply to the stator 330, thereby reducing power consumption and reducing the heat generation of the drive device 20.

[0082] It is understood that the structure of the drive device 20 is not limited to this method. In some embodiments, the fourth shaft segment 240 of the rotating shaft 200 is also inserted through the second stator unit 333; in another embodiment, the stator 330 may have only one stator unit, which may have only the first stator unit 332 or only the second stator unit 333.

[0083] See Figure 13 The drive device of the blood pump in the second embodiment has a structure that is largely the same as that of the drive device 20 in the first embodiment, with the main difference being: In this embodiment, the mounting hole 131' has an arc-shaped concave portion 131c on its wall, which is opposite to the arc-shaped convex surface 211'. The curvature of the concave portion 131c is smaller than that of the arc-shaped convex surface 211'. When the first shaft segment 210' contacts the wall of the mounting hole 131', the inflection point (line PP') of the arc-shaped convex surface 211' still contacts the concave portion 131c, forming a point-to-surface contact.

[0084] In the illustrated embodiment, the concave portion 131c is positioned opposite the second arcuate portion 213' of the arcuate convex portion 211'; the curvature of the concave portion 131c is less than that of the second arcuate portion 213'. The wall of the mounting hole 131' opposite to the first arcuate portion 212' can be a straight wall extending parallel to the axis of the first shaft segment 210', an inclined wall inclined relative to the axis of the first shaft segment 210', or an arcuate concave wall; when the wall of the mounting hole 131' opposite to the first arcuate portion 212' is an arcuate concave wall, the curvature of the wall of the mounting hole 131' opposite to the first arcuate portion 212' can be the same as or different from that of the concave portion 131c. The first arcuate portion 212' is closer to the second shaft segment 220' of the rotating shaft than the second arcuate portion 213'.

[0085] Since the driving device of this embodiment has a similar structure to the driving device of the first embodiment, the driving device of this embodiment and the blood pump having the driving device of the second embodiment also have similar effects to the first embodiment.

[0086] See Figure 14 The drive device of the blood pump in the third embodiment has a structure that is largely the same as that of the drive device 20 in the first embodiment, with the main difference being: In this embodiment, along the axial direction of the first shaft segment 210′′ and towards the impeller, the width of the gap between the arcuate convex surface 211′′ and the wall of the mounting hole 131′′ gradually decreases. That is, compared to the arcuate convex surface 211 on the first shaft segment 210 of the drive device 20 in the first embodiment, the arcuate convex surface 211′′ in this embodiment only has a first arcuate portion. At this time, the position of the inflection point PP′ of the arcuate convex surface 211′′ is located at the end of the arcuate convex surface 211′′ away from the second shaft segment 220′′. In the illustrated embodiment, the position of the inflection point PP′ of the arcuate convex surface 211′′ is exactly flush with the plane where the opening of the mounting hole 131′′ is located at the end near the impeller.

[0087] It should be noted that in some embodiments, the position of PP′ at the inflection point of the arc-shaped convex surface 211′′ can be lower than the plane containing the opening of the mounting hole 131′′ at the end near the impeller. PP′ at the inflection point of the arc-shaped convex surface 211′′ is still contained within the mounting hole 131′′, while the opening of the mounting hole 131′′ at the end near the impeller is closer to the impeller than the position of PP′ at the inflection point of the arc-shaped convex surface 211′′. That is, similar to... Figure 9 As shown, the distance H between the position of PP′ at the inflection point of the arc-shaped convex surface 211′′ and the plane containing the opening of the mounting hole 131′′ near the impeller end satisfies 0.1mm≤H≤0.2mm.

[0088] Since the driving device of this embodiment has a similar structure to the driving device of the first embodiment, the driving device of this embodiment and the blood pump having the driving device of the second embodiment also have similar effects to the first embodiment.

[0089] See Figure 15 The drive device of the blood pump in the fourth embodiment has a structure that is largely the same as that of the drive device 20 in the first embodiment, with the main difference being: In this embodiment, the arcuate convex surface 211′′′ on the first shaft segment 210′′′ has a structure similar to the arcuate convex surface 211 in the first embodiment, and also has a first arcuate portion 212′′′ and a second arcuate portion 213′′′ connected to the first arcuate portion 212′′′. The first arcuate portion 212′′′ of the arcuate convex surface 211′′′ is located inside the mounting hole 131′′′, and at least a portion of the second arcuate portion 213′′′ is located outside the mounting hole 131′′′. The distance H between the position of the inflection point PP′ of the arcuate convex surface 211′′′ and the plane containing the opening of the mounting hole 131′′′ near the impeller end is similar to (similar to) Figure 9 (as shown) less than or equal to 0.2 mm, further defined as 0.1 mm ≤ H ≤ 0.2 mm.

[0090] Since the driving device of this embodiment has a similar structure to the driving device of the first embodiment, the driving device of this embodiment and the blood pump having the driving device of this embodiment also have similar effects to the first embodiment.

[0091] See Figure 16 The drive device of the blood pump in the fifth embodiment has a structure that is generally the same as that of the drive device 20 in the first embodiment, with the main difference being: In the illustrated embodiment, the first shaft segment 210′′′′ has a first column portion 214 housed within the housing assembly 110′′′′ and a second column portion 215 connected to the first column portion 214 and located outside the housing assembly 110. The second column portion 215 is used for fixed connection with the impeller, and the second column portion 215 is coaxially arranged with the first column portion 214. The circumferential surface of the second column portion 215 near the end of the first column portion 214 is a cylindrical surface 215a, and an arcuate convex surface 211′′′′ is located at the end of the first column portion 214 near the second column portion 215. The arcuate convex surface 211′′′′ is connected to the cylindrical surface 215a, and the connection point between the arcuate convex surface 211′′′′ and the cylindrical surface 215a is the inflection point PP′ of the arcuate convex surface 211′′′′. The inflection point PP′ of the arcuate convex surface 211′′′′ is flush with the plane containing the opening of the mounting hole 131′′′′ near the impeller. Specifically, the diameter of the end of the second column portion 215 closest to the first column portion 214 is equal to the diameter of the first column portion 214 at the inflection point PP′ of the arcuate convex surface 211′′′′. That is, in this embodiment, the arcuate convex surface 211′′′′ still only has a first arcuate portion. The arcuate convex surface 211′′′′ is located at the end of the first column portion 214 furthest from the second shaft segment 220′′′′.

[0092] Since the driving device of this embodiment has a similar structure to the driving device of the first embodiment, the driving device of this embodiment and the blood pump having the driving device of this embodiment also have similar effects to the first embodiment.

[0093] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0094] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A driving device for driving an impeller to rotate, characterized in that, The driving device includes: The housing assembly is provided with mounting holes; and The rotating shaft includes a first shaft segment and a second shaft segment connected to one end of the first shaft segment. The first shaft segment is rotatably inserted through the mounting hole. The end of the first shaft segment away from the second shaft segment is used to be fixedly connected to the impeller. The first shaft segment has an arc-shaped convex surface in its circumferential direction, which protrudes radially away from the axis of the first shaft segment. The point where the arc-shaped convex surface is at its maximum distance from the axis of the first shaft segment is the inflection point of the arc-shaped convex surface. At least a portion of the arc-shaped convex surface is located in the mounting hole. The inflection point is opposite to the wall of the mounting hole, and the gap between the arc-shaped convex surface and the wall of the mounting hole is minimal at the inflection point. When the first shaft segment contacts the wall of the mounting hole, the inflection point is in contact with the wall of the mounting hole.

2. The driving device according to claim 1, characterized in that, The arc-shaped convex surface has a first arc-shaped portion and a second arc-shaped portion connected to the first arc-shaped portion, the first arc-shaped portion being located within the mounting hole; the second arc-shaped portion and the first arc-shaped portion are arranged along the axial direction of the first shaft segment, and the connection point between the second arc-shaped portion and the first arc-shaped portion is the inflection point; along the axial direction of the first shaft segment and towards the impeller, the distance from the first arc-shaped portion to the axis of the first shaft segment gradually increases, and the distance from the second arc-shaped portion to the axis of the first shaft segment gradually decreases.

3. The driving device according to claim 2, characterized in that, The entire arc-shaped convex surface is located within the mounting hole; along the axis of the first shaft segment and towards the impeller, the width of the gap between the first arc-shaped surface and the wall of the mounting hole gradually decreases, while the width of the gap between the second arc-shaped surface and the wall of the mounting hole gradually increases. Alternatively, the second arcuate portion may be located outside the mounting hole.

4. The driving device according to claim 1, characterized in that, The arc-shaped convex surface is continuously arranged around the axis of the first shaft segment; or, multiple spaced arc-shaped convex surfaces are arranged along the axial direction of the first shaft segment.

5. The driving device according to claim 1, characterized in that, The distance H between the inflection point of the arcuate convex surface and the plane containing the opening of the mounting hole near the impeller is defined along the axial direction of the first shaft segment. The value of H is in the range of H≤0.2mm.

6. The driving device according to claim 1, characterized in that, The mounting hole has an arc-shaped concave portion on its wall that is opposite to the arc-shaped convex surface. The curvature of the concave portion is smaller than that of the arc-shaped convex surface. When the first shaft segment contacts the wall of the mounting hole, the inflection point of the arc-shaped convex surface contacts the concave portion.

7. The driving device according to claim 6, characterized in that, The concave portion is positioned opposite to the second arc-shaped portion, and the curvature of the concave portion is less than that of the second arc-shaped portion; the wall of the mounting hole opposite to the first arc-shaped portion is a straight wall extending parallel to the axis of the first shaft segment.

8. The driving device according to claim 1, characterized in that, The mounting hole has a first hole portion and a second hole portion that are connected. The diameter of the first hole portion is constant, and the diameter of the second hole portion gradually decreases along the direction close to the first hole portion. The first shaft segment passes through the first hole portion and the second hole portion. The inflection point of the arc-shaped convex surface is opposite to the hole wall of the first hole portion. When the first shaft segment contacts the hole wall of the mounting hole, the inflection point of the arc-shaped convex surface contacts the hole wall of the first hole portion.

9. The driving device according to claim 1, characterized in that, The rotating shaft also includes a third shaft segment connected to the second shaft segment away from the first shaft segment; The housing assembly also has a limiting cavity and a through hole. The limiting cavity communicates with the mounting hole, and the through hole communicates with the limiting cavity. The second shaft segment is rotatably housed in the limiting cavity, and the third shaft segment is rotatably inserted through the through hole. The cross-sectional dimension of the second shaft segment is larger than the diameter of the mounting hole and the diameter of the through hole.

10. The driving device according to claim 9, characterized in that, The housing assembly further includes a receiving cavity communicating with the through hole. The rotating shaft also includes a fourth shaft segment connected to the end of the third shaft segment away from the second shaft segment. The fourth shaft segment is received within the receiving cavity and is thinner than the third shaft segment. The driving device further includes a rotor and a stator received within the receiving cavity. The rotor is fixedly connected to the fourth shaft segment, and the stator is capable of driving the rotor to rotate. The rotor is capable of driving the rotating shaft to rotate, and the fourth shaft segment is at least partially received within the stator.

11. The driving device according to claim 10, characterized in that, The rotor is magnetic, and the stator includes a first stator unit and a second stator unit. Both the first stator unit and the second stator unit can generate a rotating magnetic field that drives the rotor to rotate. The first stator unit, the rotor, and the second stator unit are arranged sequentially along the axis of the fourth shaft segment. The fourth shaft segment is rotatably inserted through the first stator unit. The rotor is fixed to the end of the fourth shaft segment away from the third shaft segment. The second stator unit and the rotating shaft are spaced apart along the axis of the fourth shaft segment, such that the fourth shaft segment does not penetrate into the second stator unit. Both the first stator unit and the second stator unit have multiple coil windings. The multiple coil windings of the first stator unit are arranged around the fourth shaft segment, and the multiple coil windings of the second stator unit are arranged around the axis of the fourth shaft segment. Both the coil windings of the second stator unit and the coil windings of the first stator unit have magnetic columns. The cross-sectional dimension of the magnetic column of the second stator unit is larger than that of the magnetic column of the first stator unit.

12. The driving device according to claim 9, characterized in that, The limiting cavity has two cavity wall surfaces along the axial direction of the rotating shaft, which are a first limiting surface and a second limiting surface; the second shaft segment is located between the first limiting surface and the second limiting surface; wherein the distance between the first limiting surface and the second limiting surface is greater than the axial length of the second shaft segment; or, the two ends along the axial direction of the second shaft segment are provided with chamfers.

13. A driving device for driving an impeller to rotate, characterized in that, The driving device includes: The housing assembly is provided with mounting holes; and The rotating shaft includes a first shaft segment for fixed connection with the impeller and rotatably passing through the mounting hole. The first shaft segment has a first column portion housed in the housing assembly and a second column portion connected to the first column portion and located outside the housing assembly. The second column portion is used for fixed connection with the impeller and is coaxially arranged with the first column portion. The first shaft segment has a circumferentially convex surface, which is located at one end of the first column near the second column. The convex surface protrudes radially away from the axis of the first shaft segment. The convex surface has a first arcuate portion, which gradually increases in distance from the axis of the first shaft segment along the axial direction of the first shaft segment and towards the impeller. The point where the distance between the first arcuate portion and the axis of the first shaft segment is the maximum is the inflection point of the convex surface. The first arcuate portion is located in the mounting hole, and the inflection point is opposite to the wall of the mounting hole. At the inflection point, the gap between the convex surface and the wall of the mounting hole is the smallest. When the first shaft segment contacts the wall of the mounting hole, the inflection point contacts the wall of the mounting hole.

14. The driving device according to claim 13, characterized in that, The inflection point is flush with the plane of the opening at the end of the mounting hole closest to the impeller.

15. The driving device according to claim 13, characterized in that, The circumferential surface of the second column near the end of the first column is a cylindrical surface. The first arcuate surface is located at the end of the first column near the second column. The first arcuate surface is connected to the cylindrical surface. The connection point between the first arcuate surface and the cylindrical surface is the inflection point.

16. The driving device according to claim 13, characterized in that, The mounting hole has a first hole portion and a second hole portion that are connected. The diameter of the first hole portion is constant. The diameter of the second hole portion gradually decreases along the direction close to the first hole portion. The first shaft segment passes through the first hole portion and the second hole portion. The inflection point is opposite to the hole wall of the first hole portion. When the first shaft segment contacts the hole wall of the mounting hole, the inflection point contacts the hole wall of the first hole portion.

17. The driving device according to claim 13, characterized in that, The rotating shaft further includes a second shaft segment connected to one end of the first shaft segment, and a third shaft segment connected to the second shaft segment away from the first shaft segment. The end of the first shaft segment away from the second shaft segment is used to be fixedly connected to the impeller. The housing assembly also has a limiting cavity and a through hole. The limiting cavity communicates with the mounting hole, and the through hole communicates with the limiting cavity. The second shaft segment is rotatably housed in the limiting cavity, and the third shaft segment is rotatably inserted through the through hole. The cross-sectional dimension of the second shaft segment is larger than the diameter of the mounting hole and the diameter of the through hole.

18. The driving device according to claim 17, characterized in that, The housing assembly further includes a receiving cavity communicating with the through hole. The rotating shaft also includes a fourth shaft segment connected to the end of the third shaft segment away from the second shaft segment. The fourth shaft segment is received within the receiving cavity and is thinner than the third shaft segment. The driving device further includes a rotor and a stator received within the receiving cavity. The rotor is fixedly connected to the fourth shaft segment, and the stator is capable of driving the rotor to rotate. The rotor is capable of driving the rotating shaft to rotate, and the fourth shaft segment is at least partially received within the stator.

19. The driving device according to claim 18, characterized in that, The rotor is magnetic, and the stator includes a first stator unit and a second stator unit. Both the first stator unit and the second stator unit can generate a rotating magnetic field that drives the rotor to rotate. The first stator unit, the rotor, and the second stator unit are arranged sequentially along the axis of the fourth shaft segment. The fourth shaft segment is rotatably inserted through the first stator unit. The rotor is fixed to the end of the fourth shaft segment away from the third shaft segment. The second stator unit and the rotating shaft are spaced apart along the axis of the fourth shaft segment, such that the fourth shaft segment does not penetrate into the second stator unit. Both the first stator unit and the second stator unit have multiple coil windings. The multiple coil windings of the first stator unit are arranged around the fourth shaft segment, and the multiple coil windings of the second stator unit are arranged around the axis of the fourth shaft segment. Both the coil windings of the second stator unit and the coil windings of the first stator unit have magnetic columns. The cross-sectional dimension of the magnetic column of the second stator unit is larger than that of the magnetic column of the first stator unit.

20. A blood pump, characterized in that, It includes an impeller and a drive device according to any one of claims 1-19, wherein the impeller is fixed to the first shaft section and the impeller is rotatable with the shaft.

21. The blood pump according to claim 20, characterized in that, The blood pump also includes a cannulation assembly, which is connected to the distal end of the drive device, and the impeller is rotatably disposed within the cannulation assembly; the cannulation assembly has an inlet and an outlet; The blood pump also includes a catheter connected to the proximal end of the drive device, the catheter being used to accommodate various supply lines.

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