Drive device and blood pump

Abstract

A blood pump (1) and a drive device (20) are disclosed. The drive device (20) includes a housing assembly (100) and a rotating shaft (200). The housing assembly (100) is provided with a mounting hole (131). The rotating shaft (200) includes a first shaft segment (210). An arc-shaped convex surface (211) is provided in the circumferential direction of the first shaft segment (210). At least a part of the arc-shaped convex surface (211) is located in the mounting hole (131). The inflection point of the arc-shaped convex surface (211) faces the hole wall of the mounting hole (131). At the inflection point, the gap between the arc-shaped convex surface (211) and the hole wall of the mounting hole (131) is the smallest. When the first shaft segment (210) contacts the hole wall of the mounting hole (131), the inflection point contacts the hole wall of the mounting hole (131).

Description

Technical Field

[0001] (Cross - reference to related applications) This application claims the priority of a Chinese patent application with application number 202210650440.6, filed with the China National Intellectual Property Administration on June 10, 2022, and all of its content is incorporated herein by reference.

[0002] This application relates to the technical field of medical devices, and particularly to a driving device and a blood pump.

Background Art

[0003] An intravascular blood pump is a blood pumping device that can enter a patient's heart through the patient's blood vessels. The intravascular blood pump is placed within the opening of the heart valve so that blood flows through the blood pump and into the arterial blood vessels. The blood pump includes a driving device and an impeller. The impeller is fixed to the rotating shaft of the driving device, and the rotating shaft drives the impeller to rotate. However, in conventional driving devices, there is usually significant wear on the rotating shaft.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Based on this, this application provides a driving device and a blood pump that can reduce wear of the rotating shaft.

Means for Solving the Problems

[0005] An embodiment of the first aspect of this application provides a driving device for driving an impeller to rotate. The driving device includes a housing assembly provided with mounting holes, and A rotating shaft configured to be fixedly connected to the impeller and including a first shaft segment rotatably penetrating through the mounting hole, wherein an arcuate convex surface is provided in the circumferential direction of the first shaft segment, at least a part of the arcuate convex surface is located in the mounting hole, an inflection point of the arcuate convex surface faces the hole wall of the mounting hole, and at the inflection point of the arcuate convex surface, the gap between the arcuate convex surface and the hole wall of the mounting hole is the smallest, and 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, including a rotating shaft.

[0006] An embodiment of the second aspect of the present application provides a blood pump including an impeller and a drive device. The drive device A housing assembly provided with a mounting hole, A rotating shaft configured to be fixedly connected to the impeller and including a first shaft segment rotatably penetrating through the mounting hole, wherein an arcuate convex surface is provided in the circumferential direction of the first shaft segment, at least a part of the arcuate convex surface is located in the mounting hole, an inflection point of the arcuate convex surface faces the hole wall of the mounting hole, and at the inflection point of the arcuate convex surface, the gap between the arcuate convex surface and the hole wall of the mounting hole is the smallest, and 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, including a rotating shaft, The impeller is fixedly connected to the first shaft segment and is rotatable together with the rotating shaft.

[0007] Details of one or more embodiments of the present invention are described in the following drawings and description. Other features, objects, and advantages of the present invention will become apparent from the specification, drawings, and claims.

Brief Description of the Drawings

[0008] In the following, in order to more clearly explain the technical solutions in the embodiments of this application, the drawings necessary for the description of the embodiments or the prior art will be briefly introduced. As is obvious, the drawings in the following description are only some embodiments of this application, and for those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0009]

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Modes for Carrying Out the Invention

[0010] Hereinafter, in order to more clearly understand the object, technical solution and advantages of the present application, the present application will be described in more detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described in this specification are only for interpreting the present application and do not limit the present application.

[0011] In addition, when an element is referred to as being "fixed to" or "provided with" another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or indirectly connected to the other element.

[0012] Also, the terms "first" and "second" are for illustrative purposes only and should not be understood as indicating relative importance or implying, or implicitly indicating the number of technical features shown. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present application, "a plurality" means two or more unless otherwise specified.

[0013] Hereinafter, in order to explain the technical means of the present application, it will be described with reference to specific drawings and embodiments.

[0014] In this specification, one end close to the operator is defined as the "proximal end", and one end away from the operator is defined as the "distal end".

[0015] As shown in FIGS. 1 and 2, the blood pump 1 according to the first embodiment of the present invention includes a driving 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 driving device 20, the catheter 42 is connected to the proximal end of the driving device 20, the impeller 41 is rotatably provided within the cannula assembly 30, the impeller 41 is connected to the driving device 20, and the driving device 20 can drive the impeller 41 to rotate to realize the blood pumping function of the blood pump 1.

[0016] Specifically, the cannula assembly 30 has an inlet 301 and an outlet 302. The outlet 302 is closer to the driving device 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 penetrates a heart valve, for example, the aortic valve, the inlet 301 is located within the heart, and the outlet 302 and the driving device 20 are located within a blood vessel such as the aorta outside the heart. When the impeller 41 rotates, blood flows into the cannula assembly 30 through the inlet 301, and then flows out of the cannula assembly 30 through the outlet 302 and into a blood vessel such as the aorta.

[0017] In some embodiments, the cannula assembly 30 includes an insertion tube 31 and an outlet tube 32. Both the insertion tube 31 and the outlet tube 32 are fixedly connected, and the outlet tube 32 is connected between the insertion tube 31 and the driving device 20. That is, 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 driving device 20. The inlet 301 is formed in the insertion tube 31, and the outlet 302 is formed in the outlet tube 32. The impeller 41 is accommodated in the outlet tube 32, and the position of the impeller 41 generally corresponds to the position of the outlet 302.

[0018] The catheter 42 is fitted to one end away from the cannula assembly 30 of the drive device 20. The catheter 42 accommodates various supply lines, and the supply lines may be, for example, a cleaning line for introducing a cleaning liquid into the drive device 20, may be, for example, a conducting wire for supplying power to the drive device 20, or may be, for example, a support member for supporting the catheter 42 or the like.

[0019] As shown in FIG. 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, the rotating shaft 200 is rotatably provided through the mounting hole 131, the impeller 41 is fixedly connected to the rotating shaft 200, both the stator 330 and the rotor 340 are accommodated in 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, the rotor 340 can drive the rotating shaft 200 to rotate, and the impeller 41 can rotate together with the rotating shaft 200 to realize the blood pumping function of the blood pump 1. The conducting wire in the catheter 42 extends into the housing assembly 100 and is electrically connected to the stator 330 to supply power to the stator 330.

[0020] In the illustrated embodiment, the housing assembly 100 includes a pump housing 110, a shaft tube 120, a first shaft sleeve 130, and a second shaft sleeve 140. The pump housing 110, the shaft tube 120, the first shaft sleeve 130, and the second shaft sleeve 140 are separate before assembly, that is, the housing assembly 100 is assembled from the separate pump housing 110, shaft tube 120, first shaft sleeve 130, and second shaft sleeve 140.

[0021] The pump housing 110 has a cylindrical structure with a substantially circular cross-section. The pump housing 110 has an accommodation cavity 112, and both the stator 330 and the rotor 340 are accommodated in the accommodation cavity 112 of the pump housing 110.

[0022] One end of the shaft tube 120 is fixedly connected to the pump housing 110, and the other end is fixedly connected to the cannula assembly 30 (specifically, the outlet tube 32). The shaft tube 120 has a mounting port 121, and the mounting port 121 is located at one end of the shaft tube 120 close to the cannula assembly 30.

[0023] The first shaft sleeve 130 and the second shaft sleeve 140 are fixedly accommodated in the shaft tube 120. Both the first shaft sleeve 130 and the second shaft sleeve 140 are fixedly connected to the shaft tube 120. The first shaft sleeve 130 and the second shaft sleeve 140 are provided along the axial direction of the shaft tube 120, and the first shaft sleeve 130 is provided closer to the impeller 41 than the second shaft sleeve 140. A mounting hole 131 is formed in the first shaft sleeve 130. The rotating shaft 200 is rotatably penetrated through the first shaft sleeve 130 and the second shaft sleeve 140. Specifically, the first shaft sleeve 130 and the second shaft sleeve 140 are separate bodies, and both the first shaft sleeve 130 and the second shaft sleeve 140 can be assembled from the mounting port 121 of the shaft tube 120, that is, the maximum outer diameters of the first shaft sleeve 130 and the second shaft sleeve 140 are both slightly smaller than the diameter of the mounting port 121.

[0024] Specifically, a support protrusion 122 is provided at one end of the shaft tube 120 close to the pump housing 110. The second shaft sleeve 140 abuts against the support protrusion 122, and the first shaft sleeve 130 abuts against the second shaft sleeve 140. Thereby, the support protrusion 122 exerts a position-limiting effect on the first shaft sleeve 130 and the second shaft sleeve 140 in the axial direction of the pump housing 110, and facilitates the assembly of the first shaft sleeve 130 and the second shaft sleeve 140. In one embodiment, the support protrusion 122 is substantially annular. An adhesive injection hole 123 is further formed in the shaft tube 120, and the adhesive injection hole 123 is filled with an adhesive. The adhesive fixedly adheres the first shaft sleeve 130 and the second shaft sleeve 140 to the shaft tube 120 and fixedly connects the first shaft sleeve 130 and the second shaft sleeve 140.

[0025] As shown in FIGS. 3, 4, 5, and 6, a position limiting hole 132 is formed in the first shaft sleeve 130, and the hole diameter of the position limiting hole 132 is larger than the hole diameter of the mounting hole 131. The mounting hole 131 is closer to the impeller 41 than the position limiting hole 132. Both the position limiting hole 132 and the mounting hole 131 are provided coaxially and communicate with each other, whereby the position limiting hole 132 and the mounting hole 131 jointly form a stepped hole. The first shaft sleeve 130 has a first position limiting surface 133 that defines a part of the boundary of the position limiting hole 132. The first position limiting surface 133 may be provided perpendicular to the axial direction of the rotation shaft 200, or may be provided inclined with respect to the axial direction of the rotation shaft 200.

[0026] The second-axis sleeve 140 includes a thick segment 141 and a thin segment 142. The cross-sectional size of the thin segment 142 is smaller than that of the thick segment 141. The thick segment 141 has a contact surface 1411. In the illustrated embodiment, the outer contours of both the thin segment 142 and the thick segment 141 are circular. The fact that the cross-sectional size of the thin segment 142 is smaller than that of the thick segment 141 means that the outer diameter of the thin segment 142 is smaller than that of the thick segment 141. The thin segment 142 protrudes from the contact surface 1411. The second-axis sleeve 140 has a through hole 143. The through hole 143 extends from the end surface of one end away from the contact surface 1411 of the thin segment 142 to the side away from the contact surface 1411 of the thick segment 141, so that the through hole 143 penetrates the thick segment 141 and the thin segment 142. The aperture diameter of the position-limiting hole 132 is larger than that of the through hole 143. The thin segment 142 is accommodated in the position-limiting hole 132, and the contact surface 1411 abuts against the first-axis sleeve 130. The position-limiting effect of the contact surface 1411 and the guiding effect of the thin segment 142 can improve the mounting accuracy and mounting efficiency. The side of the thick segment 141 far from the contact surface 1411 abuts against the support protrusion 122. The end surface of one end of the thin segment 142 away from the contact surface 1411 is a second position-limiting surface 144. The second position-limiting surface 144 and the first position-limiting surface 133 are provided at an interval and face each other. Thus, the first position-limiting surface 133 and the second position-limiting surface 144 are provided at an interval along the axial direction of the rotation axis 200. The second position-limiting surface 144 may be provided perpendicular to the axial direction of the rotation axis 200 or may be inclined with respect to the axial direction of the rotation axis 200. In the illustrated embodiment, both the first position-limiting surface 133 and the second position-limiting surface 144 are perpendicular to the axial direction of the rotation axis 200, and the first position-limiting surface 133 and the second position-limiting surface 144 are parallel and face each other.

[0027] The hole wall 132a of the position limiting hole 132, the first position limiting surface 133, and the second position limiting surface 144 jointly define a position limiting cavity 150, and both the mounting hole 131 and the through hole 143 communicate with the position limiting cavity 150. In other words, the position limiting cavity 150 is actually a part of the position limiting hole 132, and the first position limiting surface 133 and the second position limiting surface 144 are two cavity wall surfaces of the position limiting cavity 150 in the axial direction of the rotation axis 200.

[0028] The rotation axis 200 is provided to penetrate through the mounting hole 131, the position limiting cavity 150, and the through hole 143. One end of the rotation axis 200 is accommodated in the pump housing 110, the other end extends into the cannula assembly 30, and is fixedly connected to the impeller 41. There are gaps for the cleaning liquid to flow between the rotation axis 200 and the hole wall of the mounting hole 131, between the rotation axis 200 and the cavity wall of the position limiting cavity 150, and between the rotation axis 200 and the hole wall of the through hole 143. The cleaning liquid can flow from the pump housing 110 through the gaps between the rotation axis 200 and the hole wall of the through hole 143, between the rotation axis 200 and the cavity wall of the position limiting cavity 150, and between the rotation axis 200 and the mounting hole 131, and then flow into the cannula assembly 30 and out through the outlet 302. The dashed arrows in Fig. 8 indicate the flow direction of the cleaning liquid, and the flow direction of the cleaning liquid is opposite to the flow direction of the blood in the cannula assembly 30. In this way, it is possible to prevent the blood in the cannula assembly 30 from flowing into the driving device 20 through the mounting hole 131. Also, the cleaning liquid plays a role in lubrication. The cleaning liquid can reduce the frictional resistance between the rotation axis 200 and the first shaft sleeve 130, the second shaft sleeve 140, and reduce the wear between the rotation axis 200 and the first shaft sleeve 130, the second shaft sleeve 140.

[0029] Note that the housing assembly 100 is not limited to the above method. In some embodiments, two or more of the pump housing 110, the shaft tube 120, the first shaft sleeve 130, and the second shaft sleeve 140 may be of an integral structure. For example, the pump housing 110 may be integrally formed with the shaft tube 120. For example, one of the first shaft sleeve 130 and the second shaft sleeve 140 may be integrally formed with the shaft tube 120. For example, the first shaft sleeve 130 may be in a disc-shaped ring structure. For example, the first shaft sleeve 130 may be composed of two separate tubular rings and a disc-shaped ring. For example, the second shaft sleeve 140 may have only a rough segment 141.

[0030] As shown in FIGS. 3, 7, 8, and 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 that are connected in sequence. The axes of the first shaft segment 210, the second shaft segment 220, the third shaft segment 230, and the fourth shaft segment 240 overlap. The first shaft segment 210 is rotatably provided through the mounting hole 131, and the first shaft segment 210 is fixedly connected to the impeller 41. The second shaft segment 220 is rotatably received in the position-limiting cavity 150. The third shaft segment 230 is rotatably provided through the through hole 143, and the fourth shaft segment 240 is received in the accommodating cavity 112 of the pump housing 110. The fourth shaft segment 240 is fixedly connected to the rotor 340.

[0031] A part of the first shaft segment 210 is accommodated in the housing assembly 100, and a part thereof extends into the cannula assembly 30 and is fixedly connected to the impeller 41. An arc-shaped convex surface 211 is provided in the circumferential direction of the first shaft segment 210. Specifically, the arc-shaped convex surface 211 protrudes radially in a direction away from the axis of the first shaft segment 210 (the radial direction is perpendicular to the axis of the first shaft segment 210). At least a part of the arc-shaped convex surface 211 is located in the mounting hole 131, and the inflection point of the arc-shaped convex surface 211 faces the hole wall of the mounting hole 131. At the inflection point 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. When the first shaft segment 210 contacts the hole wall of the mounting hole 131, the inflection point of the arc-shaped convex surface 211 contacts the hole wall of the mounting hole 131. During the rotation of the rotating shaft 200, due to a certain radial swing, when the rotating shaft 200 swings, the first shaft segment 210 contacts the hole wall of the mounting hole 131. The larger the contact area between the first shaft segment 210 and the hole wall of the mounting hole 131, the greater the wear of the first shaft segment 210. By providing the arc-shaped convex surface 211 in the circumferential direction of the first shaft segment 210 on the rotating shaft 200, when the first shaft segment 210 contacts the hole wall of the mounting hole 131, only the inflection point of the arc-shaped convex surface 211 contacts the hole wall of the mounting hole 131, resulting in point-surface contact, 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.

[0032] Note that the inflection point of the arc-shaped convex surface 211 in this application refers to the location where the distance from the arc-shaped convex surface 211 to 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 segment 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 overlap, the axis OO' of the first shaft segment 210 is the axis of the rotating shaft 200 and is also the axes of the second shaft segment 220, the third shaft segment 230, and the fourth shaft segment 240.

[0033] Specifically, the arc-shaped convex surface 211 is provided so as to surround the axis OO' of the first shaft segment 210, and the arc-shaped convex surface 211 of this type can facilitate the manufacture of the rotating shaft 200. In the illustrated embodiment, the arc-shaped convex surface 211 is continuously provided so as to surround the axis of the first shaft segment 210. In addition, in other embodiments, a plurality of arc-shaped convex surfaces 211 spaced apart in the axial direction of the first shaft segment 210 may be provided.

[0034] In some embodiments, the width of the gap from the inflection point (line segment PP') of the arc-shaped convex surface 211 to the hole wall of the mounting hole 131 is 2 μm or less. The smallest red blood cells (with a diameter of about 8 μm and a thickness of about 2 μm) are difficult to enter a gap with a width of 2 μm or less, and the backwashed cleaning liquid passes through this gap, so blood is prevented from flowing into this gap.

[0035] Specifically, along the axial direction of the first shaft segment 210, when the distance from the inflection point (line segment PP') of the arc-shaped convex surface 211 to the plane where the opening at one end close to the impeller 41 of the mounting hole 131 is located is H, the range of the value of H is H ≤ 0.2 mm. In the illustrated embodiment, the plane where the opening at one end close to the impeller 41 of the mounting hole 131 is located is perpendicular to the axial direction of the first shaft segment 210, or perpendicular to the axis OO' of the first shaft segment 210. Further, 0.1 mm ≤ H ≤ 0.2 mm, the inflection point (line segment PP') of the arc-shaped convex surface 211 is located within the mounting hole 131 and is slightly lower than the opening at one end close to the impeller 41 of the mounting hole 131, and the hole wall of the mounting hole 131 has a better supporting effect on the rotating shaft 200. When the rotating shaft 200 contacts the hole wall of the mounting hole 131, only the inflection point (line segment PP') of the arc-shaped convex surface 211 contacts the hole wall of the mounting hole 131, while ensuring the strength of the cleaning force of the cleaning liquid.

[0036] Specifically, the arc-shaped convex surface 211 has a first arc surface portion 212 and a second arc surface portion 213 connected to the first arc surface portion 212. The first arc surface portion 212 and the second arc surface portion 213 are provided along the axial direction of the first axis segment 210. The connection location between the first arc surface portion 212 and the second arc surface portion 213 is the inflection point location (line segment PP') of the arc-shaped convex surface 211. Along the axial direction of the first axis segment 210 and in the direction approaching the impeller 41, the distance from the first arc surface portion 212 to the axis OO' of the first axis segment 210 gradually increases, and the distance from the second arc surface portion 213 to the axis OO' of the first axis segment 210 gradually decreases. In the illustrated embodiment, the entire arc-shaped convex surface 211 is located within the mounting hole 131. Along the axis OO' of the first axis segment 210 and in the direction approaching the impeller 41, the width of the gap between the first arc surface portion 212 and the hole wall of the mounting hole 131 gradually decreases, and the width of the gap between the second arc surface portion 213 and the hole wall of the mounting hole 131 gradually increases. At the connection location between the first arc surface portion 212 and the second arc surface portion 213, that is, at the line segment PP', the width of the gap between the arc-shaped convex surface 211 and the hole wall of the mounting hole 131 is the smallest.

[0037] In some embodiments, in order to prevent red blood cells in the blood from entering between the first axis segment 210 and the hole wall of the mounting hole 131, the width of the gap between the hole wall of the opening at one end of the mounting hole 131 close to the impeller 41 and the first axis segment 210 is 2 μm or less. Thereby, the width of the gap between the inflection point location (line segment PP') of the arc-shaped convex surface 211 and the hole wall of the mounting hole 131 is less than 2 μm, that is, smaller than the width of the gap between the hole wall of the opening at one end of the mounting hole 131 close to the impeller 41 and the first axis segment 210.

[0038] Note that the width of the gap between the inflection point location of the arc-shaped convex surface 211 and the hole wall of the mounting hole 131, and the width of the gap between the hole wall of the opening at one end of the mounting hole 131 close to the impeller 41 and the first axis segment 210 may be adjusted according to requirements and design.

[0039] In order to facilitate the inflow of the cleaning liquid from the position-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 communicate with each other. The diameter of the first hole portion 131a is constant, and along the direction approaching the first hole portion 131a, the diameter of the second hole portion 131b gradually decreases. The first shaft segment 210 is provided to penetrate through the first hole portion 131a and the second hole portion 131b. The inflection point (line segment PP') of the arc-shaped convex surface 211 faces 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 segment PP') of the arc-shaped convex surface 211 contacts the hole wall of the first hole portion 131a. That is, the diameter of one end of the second hole portion 131b close to the position-limiting cavity 150 is larger than the diameter of the first hole portion 131a. The first hole portion 131a with a constant diameter better supports the rotating shaft 200 and can reduce the swing range of the rotating shaft 200. The second hole portion 131b with a diameter changing as described above can play a guiding role for the cleaning liquid so that the cleaning liquid can flow into the mounting hole 131.

[0040] In some embodiments, an internal chamfer is formed on the hole wall of one end of the through hole 143 close to the position-limiting cavity 150, which is beneficial for reducing the contact area between the rotating shaft 200 and the second shaft sleeve 140 and reducing the wear of the rotating shaft 200.

[0041] The second shaft segment 220 is fixedly connected to one end of the first shaft segment 210 away from the impeller 41. The second shaft segment 220 is rotatably accommodated in the position-limiting cavity 150. In other words, the cross-sectional size of the second shaft segment 220 is smaller than the cross-sectional size of the position-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. Thereby, the second shaft segment 220 is limited by the position-limiting cavity 150. In this way, the second shaft segment 220 does not enter the through hole 143 and the mounting hole 131, and the second shaft segment 220 is located between the first position-limiting surface 133 and the second position-limiting surface 144, thereby limiting the position of the rotating shaft 200 in the axial direction of the rotating shaft 200.

[0042] Specifically, the second shaft segment 220 can abut against the first position limiting surface 133 and the second position limiting surface 144 to prevent the axial movement of the rotating shaft 200 or limit the axial movement distance thereof. In some embodiments, the second shaft segment 220 is always slidably abutted against the first position limiting surface 133 and the second position limiting surface 144. In some other embodiments, the interval between the first position limiting surface 133 and the second position 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 for the cleaning liquid to flow between the first position limiting surface 133 and the second position limiting surface 144. A circulation gap 151 for the cleaning liquid to flow through is formed between the second shaft segment 220 and the cavity wall extending along the axis OO' of the position limiting cavity 150.

[0043] As shown in FIGS. 4, 5 and 6, further, a part of the first position limiting surface 133 is recessed to form a first diversion groove 1331, and the first diversion groove 1331 extends from the hole wall 1311 of the mounting hole 131 towards the hole wall 132a of the position limiting hole 132, so that the first diversion groove 1331 communicates the mounting hole 131 and the position limiting hole 132. Since the position limiting cavity 150 is a part of the position limiting hole 132, the first diversion groove 1331 also communicates with the position limiting cavity 150. A part of the second position limiting surface 144 is recessed to form a second diversion groove 1441, and the second diversion groove 1441 extends from the hole wall 1311 of the through hole 143 to the outer peripheral surface of the thin segment 142, and the second diversion groove 1441 communicates the through hole 143 and the position limiting cavity 150. Since the circulation gap 151 is actually a part of the position limiting cavity 150, the circulation gap 151 communicates the first diversion groove 1331 and the second diversion groove 1441 simultaneously. By providing the first diversion groove 1331 and the second diversion groove 1441, it is advantageous for the flow of the cleaning liquid.

[0044] In addition, in some embodiments, only one of the first diversion groove 1331 and the second diversion groove 1441 may be provided, or neither the first diversion groove 1331 nor the second diversion groove 1441 may be provided.

[0045] In some embodiments, chamfers 222 are provided at both axial ends of the second shaft segment 220. In this way, on the one hand, the contact area between the rotating shaft 200 and the first position limiting surface 133 and / or the second position limiting surface 144 is reduced, and further, the contact area between the rotating shaft 200 and the first shaft sleeve 130 and the second shaft sleeve 140 is reduced, and further, the wear of the rotating shaft 200 is reduced. On the other hand, the sharp edges of the second shaft segment 220 that contact the first shaft sleeve 130 and the second shaft sleeve 140 are prevented from wearing the first shaft sleeve 130 and the second shaft sleeve 140, and a flow guiding effect on the cleaning liquid can be achieved.

[0046] The third shaft segment 230 is rotatably provided through the through hole 143. There is a gap through which the cleaning liquid flows between the third shaft segment 230 and the hole wall of the through hole 143.

[0047] The fourth shaft segment 240 is connected to one end of the third shaft segment 230 away from the second shaft segment 220. The fourth shaft segment 240 is accommodated in the accommodation cavity 112. The cross-sectional size of the fourth shaft segment 240 is smaller than the cross-sectional size of the third shaft segment 230. The rotor 340 is fixedly connected to the fourth shaft segment 240. At least a part of the fourth shaft segment 240 is accommodated in the stator 330.

[0048] Specifically, the rotating shaft 200, the first shaft sleeve 130, and the second shaft sleeve 140 may be made of a ceramic material, thereby improving the wear resistance of the rotating shaft 200, the first shaft sleeve 130, and the second shaft sleeve 140, and further preventing the wear of the rotating shaft 200, the first shaft sleeve 130, and the second shaft sleeve 140.

[0049] Furthermore, as shown in FIG. 3, the stator 330 includes a first stator unit 332 and a second stator unit 333, and both the first stator unit 332 and the second stator unit 333 can drive the rotor 340 to rotate. Specifically, the first stator unit 332 and the second stator unit 333 are provided at intervals along the extending direction of the rotating shaft 200. The first stator unit 332 and the second stator unit 333 are both fixedly connected to the housing assembly 100. The fourth shaft segment 240 of the rotating shaft 200 is rotatably penetrated through the first stator unit 332. That is, the rotor 340 is rotatable with respect to the housing assembly 100, and the first stator unit 332 and the second stator unit 333 are non-rotatable with respect to the housing assembly 100.

[0050] The first stator unit 332 and the second stator unit 333 may be connected in parallel or in series. In some embodiments, the first stator unit 332 and the second stator unit 333 can drive the rotor 340 to rotate synchronously. The first stator unit 332 and the second stator unit 333 can both drive the rotor 340 to rotate, and can also drive the rotor 340 to rotate alone.

[0051] In some embodiments, the rotor 340 has magnetism, and the stator 330 can generate a rotating magnetic field that drives the rotor 340 to rotate. Specifically, both the first stator unit 332 and the second stator unit 333 can generate a rotating magnetic field that drives the rotor 340 to rotate.

[0052] 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 fixedly connected to the housing assembly 100. In the illustrated embodiment, the first back plate 3323 is fixedly connected to the shaft tube 120. There are a plurality of first magnetic cores 3321, and the plurality of first magnetic cores 3321 are provided at intervals along the circumference. Specifically, the extending direction of each first magnetic core 3321 coincides with the extending direction of the rotation axis 200. Each first magnetic core 3321 is fixedly connected 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 one coil winding. Then, the plurality of coil windings of the first stator unit 332 are provided so as to go around the fourth shaft segment 240 once.

[0053] The structure of the second stator unit 333 is the same as 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 fixedly connected to the housing assembly 100. There are a plurality of second magnetic cores 3331, and the plurality of second magnetic cores 3331 are provided at intervals along the circumference. Specifically, the extending direction of each second magnetic core 3331 is parallel to the axis of the fourth shaft segment 240 (i.e., the axis OO'). Each second magnetic core 3331 is fixedly connected 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 one coil winding. Then, the plurality of coil windings of the second stator unit 333 are provided so as to go around the axis of the fourth shaft segment 240 (i.e., OO') once.

[0054] In some embodiments, both the first magnetic core 3321 and the second magnetic core 3331 include a magnetic column and a head (i.e., a pole piece) provided at one end of the magnetic column, and the extending direction of the magnetic column coincides with the extending direction of the rotation axis. The first back plate 3323 is joined to one end of the magnetic column of the first magnetic core 3321 away from the head, and the second back plate 3333 is joined to one end of the magnetic column of the second magnetic core 3331 away from the head. In the extending direction of the magnetic column, the magnetic column presents a columnar body with a substantially uniform size, that is, the cross-sectional size of the magnetic column 3331 is kept constant, and generally speaking, the thickness of the magnetic column 3331 is uniform. The first coil 3322 is wound around the magnetic column of the first magnetic core 3321, and the second coil 3332 is wound around the magnetic column of the second magnetic core 3331.

[0055] As shown in FIG. 3, in the illustrated embodiment, the first magnetic core 3321 and the second magnetic core 3331 include only magnetic columns, that is, the first magnetic core 3321 and the second magnetic core 3331 do not have a head (i.e., a pole piece) with a large cross section. Therefore, the magnetic column of the first stator unit 332 is the first magnetic core 3321, and the magnetic column of the second stator unit 333 is the second magnetic core 3331. In this case, the entire first magnetic core 3321 can be magnetically coupled to the rotor 340, and the entire second magnetic core 3331 can be magnetically coupled to the rotor 340. Compared with a magnetic core having a pole piece, a magnetic core having only a magnetic column can reduce magnetic loss and increase the magnetic coupling density between the magnetic core and the rotor 340, so that for the same current, the torque on the rotor 340 from the stator unit can be increased. On the other hand, a magnetic core without a head can greatly reduce the problem that the power of the driving device 20 decreases due to local magnetic short circuit caused by the contact between adjacent magnetic cores.

[0056] It should be noted that the first magnetic core 3321 and the second magnetic core 3331 are not limited to the above two methods. In some embodiments, one of the first magnetic core 3321 and the second magnetic core 3331 may have both a magnetic column and a head, and the other may have only a magnetic column.

[0057] In some embodiments, the cross-sectional shape of the magnetic poles of the first magnetic core 3321 and the second magnetic core 3331 is substantially triangular prism-shaped, and one edge of each magnetic pole faces the axis of the rotation axis. In some embodiments, the edges of the magnetic poles are all chamfered, that is, the edges of the magnetic poles are relatively smooth and blunt chamfered edges, thereby removing the sharp corners of the magnetic poles and not only facilitating the subsequent winding of the coil, but also being advantageous for protecting the insulating material coated on the coil. In other embodiments, the cross-sectional shape of the magnetic poles of the first magnetic core 3321 and the second magnetic core 3331 may be fan-shaped, circular, trapezoidal, annular fan-shaped, etc.

[0058] In the illustrated embodiment, along the axis of the fourth axis segment 240 (i.e., along the axis OO'), the rotation axis 200 is spaced apart from the second stator unit 333, that is, one end of the fourth axis segment 240 of the rotation axis 200 away from the third axis segment 230 is spaced apart from the second stator unit 333, that is, the fourth axis segment 240 of the rotation axis 200 does not penetrate the second stator unit 333. The cross-sectional size of the magnetic poles of the second stator unit 333 is larger than the cross-sectional size of the magnetic poles of the first stator unit 332.

[0059] The larger the cross-sectional area of the magnetic column, the larger the generated magnetic flux, the larger the torque on the rotor 340 from the stator unit, the smaller the required current, which is advantageous for reducing power consumption and heat generation. When the cross-sectional sizes of the first stator unit 332 and the second stator unit 333 are the same and the outer diameter of the housing assembly 100 remains unchanged, since the rotating shaft 200 is located outside the second stator unit 333 and the rotating shaft 200 is not provided to penetrate 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. In this way, the driving torque on the rotor 340 from the second stator unit 333 can be increased. When the required torque is the same, this method can reasonably reduce the current supply to the stator 330, reduce the power consumption, reduce the heat generation amount of the driving device 20, and avoid discomfort and even injury to the human body caused by heat concentration and too high temperature during the operation of the blood pump 1.

[0060] In addition, in other embodiments, the rotating shaft 200 may be inserted into the second stator unit 333. In this case, the cross-sectional sizes of the magnetic columns of the first stator unit 332 and the second stator unit 333 are the same.

[0061] The first back plate 3323 and the second back plate 3333 have a substantially flat plate-like structure. The first back plate 3323 and the second back plate 3333 are made of the same material as the first magnetic core 3321 and the second magnetic core 3331, and are made of a soft magnetic material such as cobalt steel, for example.

[0062] The back plate can play a role in closing the magnetic circuit of the stator unit, promoting and increasing the generation of magnetic flux in the stator unit, and improving the coupling ability between each stator unit and the rotor 340. In other words, by providing the first back plate 3323 on the first stator unit 332, the generation of magnetic flux in the first stator unit 332 can be promoted and increased, and the coupling ability between the first stator unit 332 and the rotor 340 can be improved. By providing the second back plate 3333 on the second stator unit 333, the generation of magnetic flux in the second stator unit 333 can be promoted and increased, and the coupling ability between the second stator unit 333 and the rotor 340 can be improved. Since the back plate can increase the magnetic flux, providing back plates on the first stator unit 332 and the second stator unit 333 respectively is advantageous for reducing the diameter of the entire drive device 20.

[0063] Specifically, the drive device 20 further includes a positioning member 360. The positioning member 360 is fixedly connected within the pump housing 110. The positioning member 360 has a positioning post 364. A positioning hole 3334 is provided in the second back plate 3333 of the second stator unit 333. The positioning post 364 is provided to penetrate through the positioning hole 3334. Thereby, the positioning member 360 can exert a positioning function on the second stator unit 333, and the mounting accuracy and mounting efficiency of the second stator unit 333 can be improved. Specifically, the central axis of the positioning post 364 and the central axis of the second stator unit 333 overlap each other. In some embodiments, a through hole 365 is further formed in the positioning member 360. The through hole 365 communicates with a cleaning line for introducing a cleaning liquid into the drive device 20 or is used for mounting the cleaning line.

[0064] In some embodiments, the first stator unit 332 may not have the first back plate 3323, the second stator unit 333 may not have the second back plate 3333, or one of the first stator unit 332 and the second stator unit 333 may have a back plate while the other may not have a back plate. When the second stator unit 333 does not have the second back plate 3333, a plurality of positioning holes can be directly formed in the positioning member 360, and one ends of the plurality of second magnetic cores 3331 are respectively positioned in the plurality of positioning holes.

[0065] In some embodiments, the positioning member 360 may be omitted. At this time, an engaging portion for engaging with the edge of the second back plate 3333 may be provided in the pump housing 110, and the fixing of the second stator unit 333 may be realized by the engagement between the engaging portion and the second back plate 3333. Alternatively, the second stator unit 333 may be adhesively fixed to the pump housing 110 with an adhesive. The first stator unit 332 may be adhesively fixed to the shaft tube 120 with an adhesive, or the fixing of the first stator unit 332 may be realized by providing a corresponding engaging portion in the pump housing 110 and engaging with the first back plate 3323.

[0066] As shown in FIGS. 3 and 10 to 12, the rotor 340 is accommodated in the accommodation cavity 112 of the pump housing 110. In the illustrated embodiment, the rotor 340 is located between the first stator unit 332 and the second stator unit 333 along the axis OO'. Specifically, the rotor 340 includes a first magnet 342 and a second magnet 343. Both the first magnet 342 and the second magnet 343 are fixedly connected 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 in sequence. The first stator unit 332 can generate a rotating magnetic field to drive the first magnet 342 to rotate, and the second stator unit 333 can generate a rotating magnetic field to drive the second magnet 343 to rotate. The two stator units can respectively provide torque to the rotor 340 through the two magnets, and the driving force for rotating the rotor 340 can be increased.

[0067] Specifically, the rotor 340 further includes a flywheel 344. The flywheel 344 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. 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 one end of the fourth shaft segment 240 away from the third shaft segment 230.

[0068] By providing the flywheel 344, the connection strength between the first magnet 342 and the second magnet 343 and the fourth shaft segment 240 can be improved. Also, by providing both the first magnet 342 and the second magnet 343 on the same flywheel 344, the sway during the rotation of the fourth shaft segment 240 can be reduced, and the fourth shaft segment 240 can be made more stable during rotation.

[0069] In the illustrated embodiment, the flywheel 344 includes an internal pipe 3442, a disk-shaped portion 3444, and an outer annular wall 3446. Both the internal pipe 3442 and the outer annular wall 3446 are of circular tubular structure, and the disk-shaped portion 3444 is of annular disk structure. The internal pipe 3442 and the outer annular wall 3446 are both fixedly connected to the disk-shaped portion 3444. The outer annular wall 3446 is provided so as to surround the disk-shaped portion 3444, and both the internal pipe 3442 and the outer annular wall 3446 are coaxially provided. The fourth axis segment 240 is provided to penetrate through the internal pipe 3442 and is fixedly connected to the internal pipe 3442. An accommodation space is formed between the internal pipe 3442 and the outer annular wall 3446, and the disk-shaped portion 3444 partitions the accommodation space into two mounting cavities 3448. Both of the two mounting cavities 3448 are annular cavities. The first magnet 342 and the second magnet 343 are respectively accommodated in the two mounting cavities 3448. The first magnet 342 and the second magnet 343 are both annular, and the shapes of the two mounting cavities 3448 are adapted to the first magnet 342 and the second magnet 343 respectively, facilitating the mounting and positioning of the first magnet 342 and the second magnet 343. In this way, the flywheel 344 can exert a position limiting effect on the first magnet 342 and the second magnet 343, not only facilitating the mounting of the first magnet 342 and the second magnet 343, but also making the connection between the first magnet 342 and the second magnet 343 and the flywheel 344 more stable.

[0070] Note that the flywheel 344 is not limited to the above structure. In some embodiments, the flywheel 344 has no outer annular wall 3446. In some embodiments, the flywheel 344 has neither an outer annular wall 3446 nor an internal pipe 3442. At this time, the fourth axis segment 240 is fixedly provided to penetrate through the disk-shaped portion 3444, for example, the center of the disk-shaped portion 3444. By providing the internal pipe 3442 for the flywheel 344 having only the disk-shaped portion 3444, the connection between the flywheel 344 and the fourth axis segment 240 can be made more stable.

[0071] In some embodiments, both the first magnet 342 and the second magnet 343 are annular Halbach array magnets. Specifically, both the first magnet 342 and the second magnet 343 include a plurality of magnetic bodies. For example, the number of magnetic bodies is 4, 6, 8, 10, etc. Each magnetic body is an annular sector. The plurality of magnetic bodies of the first magnet are provided to surround the fourth axis segment 240 to form an annular structure. The plurality of magnetic bodies of the second magnet 343 are provided to surround the rotor 340 to form an annular structure.

[0072] More specifically, the first magnet 342 has a first magnetic body 3422 magnetized along the axial direction of the first magnet 342. 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 provided on both separated sides of the disk-shaped portion 3444. The positions of the first magnetic body 3422 and the second magnetic body 3432 correspond. In the extending direction of the rotor 340, the polarities of the sides of the first magnetic body 3422 and the second magnetic body 3432 facing the disk-shaped portion 3444 are opposite. In this way, the attachment of the first magnet 342 and the second magnet 343 is facilitated, and the problem that the first magnetic body 3422 and the second magnetic body 3432 corresponding to the positions of the first magnet 342 and the second magnet 343 located at the disk-shaped portion 3444 repel each other and make assembly difficult can be avoided. For example, if the polarity of the side of the first magnetic body 3422 facing the disk-shaped portion 3444 is the N pole, the polarity of the side of the second magnetic body 3432 facing the disk-shaped portion 3444 is the S pole. According to the principle that the N pole and the S pole attract each other, the interference of the magnetic repulsive force is removed, and the attachment efficiency of the first magnet 342 and the second magnet 343 is improved.

[0073] In order to facilitate the attachment of the first magnet 342 and the second magnet 343 and improve the attachment accuracy of the first magnet 342 and the second magnet 343, the flywheel 344 is further provided with a marking portion 345 for specifying the attachment positions of the first magnetic body 3422 and the second magnetic body 4332. The marking portion 345 may be provided as a groove, a scale line, a mark, or the like. When attaching the first magnet 342 and the second magnet 343, if the positions of one magnetic body of the first magnet 342 and the second magnet 343 are respectively marked using the marking portion 445, the attachment positions of the remaining magnetic bodies can be specified, facilitating the attachment of the first magnet 342 and the second magnet 343. Specifically, the marking portion 345 is provided on at least one of the built-in tube 3442, the disk-shaped portion 3444, and the outer ring wall 3446. Specifically, in the illustrated embodiment, marking portions 345 are provided on both end faces of the built-in tube 3442.

[0074] The above drive device and blood pump have at least the following advantages.

[0075] (1) During the rotation of the rotary shaft 200, there is a certain radial sway. Therefore, when the rotary shaft 200 sways, the rotary shaft 200 comes into contact with the hole wall of the mounting hole 131. The larger the contact area between the rotary shaft 200 and the hole wall of the mounting hole 131, the greater the wear of the rotary shaft 200. An arcuate convex surface 211 is provided in the circumferential direction of the first shaft segment 210 of the rotary shaft 200 of the drive device 20. At the inflection point PP' of the arcuate convex surface 211, the gap between the arcuate convex surface 211 and the hole wall of the mounting hole 131 is the smallest. Thus, when the first shaft segment 210 comes into contact with the hole wall of the mounting hole 131 of the housing assembly 100, the inflection point PP' of the arcuate convex surface 211 comes into contact with the hole wall of the mounting hole 131, resulting in point-surface contact, 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 rotary shaft 200.

[0076] (2) Assemble the housing assembly 100 of the above structure, that is, the separate pump housing 110, the shaft tube 120, the first shaft sleeve 130, and the second shaft sleeve 140. By making the maximum outer diameter of the mounting port 121 of the shaft tube 120 slightly smaller than the aperture diameter of the mounting port 121, the assembly of the drive device 20 can be facilitated. For example, the first shaft sleeve 130, the second shaft sleeve 140, and the rotating shaft 200 can be assembled from one direction, simplifying the assembly of the drive device 20 and improving the production efficiency.

[0077] (3) Since the fourth shaft segment 240 of the rotating shaft 200 penetrates through the stator 330 and the cross-sectional size of the fourth shaft segment 240 is smaller than that of the third shaft segment 230, in order to ensure the structural strength of the entire rotating shaft 200, the occupied space of the fourth shaft segment 240 in the radial direction of the stator 330 can be reduced. When ensuring that the outer diameters of the stator 330 and the pump housing 110 remain unchanged, the cross-sectional size of the magnetic poles in the stator 330 can be reasonably increased. Generally, the magnetic poles can be designed to be reasonably thicker. The larger the cross-sectional size of the magnetic poles, the larger the magnetic flux generated, the larger the torque from the stator 330 to the rotor 340, the smaller the required current, which is beneficial to reducing power consumption and heat generation, and avoiding discomfort and even injury to the human body caused by heat concentration and too high temperature during the operation of the blood pump 1. By increasing the cross-sectional size of the third shaft segment 230, the rotating shaft 200 can have high structural strength at the through hole 143.

[0078] (4) The rotating shaft 200 of the drive device 20 is separated from the second stator unit 333 in the axial direction, and in a manner that does not increase the outer diameter of the pump housing 110, the cross-sectional size of the magnetic poles of the second stator unit 333 can be reasonably increased. In this way, the driving torque on the rotor 340 from the second stator unit 333 can be increased. When the required torque is the same, this method can reasonably reduce the current supply to the stator 330, reduce power consumption, and reduce the heat generation of the drive device 20.

[0079] Note that the structure of the drive device 20 is not limited to the above form. In some embodiments, the fourth shaft segment 240 of the rotating shaft 200 also penetrates and is provided in the second stator unit 333. In other embodiments, the stator 330 may have only one stator unit, may have only the first stator unit 332, or may have only the second stator unit 333.

[0080] As shown in FIG. 13, the drive device of the blood pump in the second embodiment is substantially the same as the structure of the drive device 20 in the first embodiment, but the main differences are as follows.

[0081] An arcuate concave portion 131c facing the arcuate convex surface 211' is provided on the hole wall of the mounting hole 131' in this embodiment. The curvature of the concave portion 131c is smaller than that of the arcuate convex surface 211'. When the first shaft segment 210' contacts the hole wall of the mounting hole 131', still the inflection point location (line segment PP') of the arcuate convex surface 211' contacts the concave portion 131c, resulting in point-surface contact.

[0082] In the illustrated embodiment, the position of the concave surface portion 131c faces the position of the second arc surface portion 213' of the arc-shaped convex surface 211', and the curvature of the concave surface portion 131c is smaller than the curvature of the second arc surface portion 213'. The hole wall of the mounting hole 131' further includes a first inner wall 131d. The first inner wall 131d faces the position of the first arc surface portion 212'. The first inner wall 131d is a straight wall extending parallel along the axis of the first axis segment 210'. The first inner wall 131d may be an inclined wall inclined with respect to the axis of the first axis segment 210', or the first inner wall 131d may be an arc-shaped concave wall. When the first inner wall 131d, which is the hole wall of the mounting hole 131' facing the position of the first arc surface portion 212', is an arc-shaped concave wall, the curvature of the hole wall of the mounting hole 131' facing the position of the first arc surface portion 212' may be the same as or different from the curvature of the concave surface portion 131c. The first arc surface portion 212' is closer to the second axis segment 220' of the rotation axis than the second arc surface portion 213'.

[0083] Since the drive device of this embodiment has the same structure as the drive device of the first embodiment, the blood pump provided with the drive device of this embodiment and the drive device of the second embodiment also has the same effects as the first embodiment.

[0084] As shown in FIG. 14, the drive device of the blood pump of the third embodiment is substantially the same as the structure of the drive device 20 of the first embodiment, but the main differences are as follows.

[0085] In this embodiment, along the axial direction of the first axis segment 210'' and in the direction approaching the impeller, the width of the gap between the arc-shaped convex surface 211'' and the hole wall of the mounting hole 131'' gradually decreases. That is, with respect to the arc-shaped convex surface 211 in the first axis segment 210 of the drive device 20 of the first embodiment, the arc-shaped convex surface 211'' of this embodiment has only the first arc surface portion. At this time, the position of the inflection point PP' of the arc-shaped convex surface 211'' is located at one end away from the second axis segment 220'' of the arc-shaped convex surface 211''. In the illustrated embodiment, the position of the inflection point PP' of the arc-shaped convex surface 211'' is flush with the plane where the opening of the end of the mounting hole 131'' close to the impeller is located.

[0086] In some embodiments, the position of the inflection point PP' of the arcuate convex surface 211'' may be lower than the plane where the opening at one end close to the impeller of the mounting hole 131'' is located. The inflection point PP' of the arcuate convex surface 211'' is still accommodated within the mounting hole 131'', and the opening at one end of the mounting hole 131'' close to the impeller is closer to the impeller than the position of the inflection point PP' of the arcuate convex surface 211''. That is, as shown in FIG. 9, the distance H from the position of the inflection point PP' of the arcuate convex surface 211'' to the plane where the opening at one end close to the impeller of the mounting hole 131'' is located satisfies 0.1 mm ≤ H ≤ 0.2 mm.

[0087] Since the drive device of this embodiment has the same structure as the drive device of the first embodiment, the blood pump provided with the drive device of this embodiment and the drive device of the third embodiment also exhibits the same effects as the first embodiment.

[0088] As shown in FIG. 15, the drive device of the blood pump of the fourth embodiment is substantially the same as the structure of the drive device 20 of the first embodiment, but the main differences are as follows.

[0089] In this embodiment, the arcuate convex surface 211''' on the first shaft segment 210''' has a structure similar to the arcuate convex surface 211 of the first embodiment, and has a first arcuate surface portion 212''' and a second arcuate surface portion 213''' connected to the first arcuate surface portion 212'''. The first arcuate surface portion 212''' of the arcuate convex surface 211''' is located within the mounting hole 131''', and at least a part of the second arcuate surface portion 213''' is located outside the mounting hole 131'''. The distance H (as shown in FIG. 9) from the position of the inflection point PP' of the arcuate convex surface 211''' to the plane where the opening at one end close to the impeller of the mounting hole 131''' is located is 0.2 mm or less, and further 0.1 mm ≤ H ≤ 0.2 mm.

[0090] Since the drive device of this embodiment has the same structure as the drive device of the first embodiment, the drive device of this embodiment and the blood pump provided therewith also exhibit the same effects as the first embodiment.

[0091] As shown in FIG. 16, the drive device of the blood pump of the fifth embodiment is substantially the same as the structure of the drive device 20 of the first embodiment, but the main differences are as follows.

[0092] In the illustrated embodiment, the first shaft segment 210'''' has a first column portion 214 housed in 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 to be fixedly connected to the impeller. The second column portion 215 is provided coaxially with the first column portion 214. The circumferential surface of one end of the second column portion 215 close to the first column portion 214 is the column surface 215a. The arc-shaped convex surface 211'''' is located at one end of the first column portion 214 close to the second column portion 215. The arc-shaped convex surface 211'''' is connected to the column surface 215a. The connection point between the arc-shaped convex surface 211'''' and the column surface 215a is the inflection point PP' of the arc-shaped convex surface 211''''. The inflection point PP' of the arc-shaped convex surface 211'''' is flush with the plane where the opening of the mounting hole 131'''''' close to the impeller is located. Specifically, the diameter of one end of the second column portion 215 close to the first column portion 214 is equal to the diameter of the first column portion 214 at the inflection point PP' of the arc-shaped convex surface 211''''. That is, in this embodiment, the arc-shaped convex surface 211'''' still has only the first arc-shaped surface portion. The arc-shaped convex surface 211'''' is located at one end of the first column portion 214 away from the second shaft segment 220''''.

[0093] Since the drive device of this embodiment has the same structure as the drive device of the first embodiment, the drive device of this embodiment and the blood pump equipped with it also have the same effects as the first embodiment.

[0094] The above embodiments are merely for explaining the technical solutions of the present invention and are not restrictive. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that the technical solutions described in each of the foregoing embodiments can be modified or equivalent replacements can be made for some of the technical features thereof. These modifications and replacements do not deviate from the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of each embodiment of the present invention, and all of them should be included in the protection scope of the present invention.

Claims

1. A driving device for driving and rotating an impeller, comprising: A housing assembly provided with a mounting hole; A rotating shaft configured to be fixedly connected to the impeller and rotatably penetrating through the mounting hole, including a first shaft segment. An arcuate convex surface is provided in the circumferential direction of the first shaft segment. At least a part of the arcuate convex surface is located in the mounting hole. The inflection point of the arcuate convex surface faces the hole wall of the mounting hole. At the inflection point of the arcuate convex surface, the gap between the arcuate convex surface and the hole wall of the mounting hole is the smallest. 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. The driving device is characterized by including a rotating shaft.

2. When the distance from the inflection point of the arcuate convex surface to the plane where the opening at one end of the mounting hole close to the impeller is located along the axial direction of the first shaft segment is H, the value range of H is H≤0.2 mm. The driving device according to claim 1 is characterized by this.

3. The arcuate convex surface has a first arcuate surface portion. The first arcuate surface portion is located in the mounting hole. Along the axial direction of the first shaft segment and in the direction approaching the impeller, the distance from the first arcuate surface portion to the axis of the first shaft segment gradually increases. The inflection point of the arcuate convex surface is located on the first arcuate surface portion. The driving device according to claim 1 is characterized by this.

4. The arcuate convex surface further has a second arcuate surface portion connected to the first arcuate surface portion. The second arcuate surface portion and the first arcuate surface portion are provided along the axial direction of the first shaft segment. The connection portion between the second arcuate surface portion and the first arcuate surface portion is the inflection point of the arcuate convex surface. Along the axial direction of the first shaft segment and in the direction approaching the impeller, the distance from the second arcuate surface portion to the axis of the first shaft segment gradually decreases. The driving device according to claim 3 is characterized by this.

5. The second arcuate surface portion is located in the mounting hole. The driving device according to claim 4 is characterized by this.

6. The position of the inflection point of the arcuate convex surface is flush with the plane where the opening at one end of the mounting hole close to the impeller is located. The driving device according to claim 1 is characterized by this.

7. 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 configured to be fixedly connected to the impeller. The second column portion is provided coaxially with the first column portion. The circumferential surface of one end of the second column portion close to the first column portion is a cylindrical surface. The arcuate convex surface is located at one end of the first column portion close to the second column portion. The arcuate convex surface is connected to the cylindrical surface, and the connection location between the arcuate convex surface and the cylindrical surface is the inflection point location of the arcuate convex surface. The drive device according to claim 6, characterized in that.

8. The entire arcuate convex surface is located within the mounting hole, and along the axial direction of the rotating shaft and in the direction approaching the impeller, the width of the gap between the arcuate convex surface and the hole wall of the mounting hole gradually decreases. The drive device according to claim 1, characterized in that.

9. The arcuate convex surface is continuously provided so as to circle around the axis of the first shaft segment. The drive device according to claim 1, characterized in that.

10. The width of the gap from the inflection point location of the arcuate convex surface to the hole wall of the mounting hole is 2 μm or less. The drive device according to claim 1, characterized in that.

11. An arcuate concave portion facing the arcuate convex surface is provided on the hole wall of the mounting hole. The curvature of the concave portion is smaller than the curvature of the arcuate convex surface. When the first shaft segment contacts the hole wall of the mounting hole, the inflection point location of the arcuate convex surface contacts the concave portion. The drive device according to claim 1, characterized in that.

12. The arcuate convex surface has a first arcuate surface portion and a second arcuate surface portion. The first arcuate surface portion and the second arcuate surface portion are provided along the axial direction of the first shaft segment. The second arcuate surface portion is closer to the impeller than the first arcuate surface portion. The connection location between the second arcuate surface portion and the first arcuate surface portion is the inflection point location of the arcuate convex surface. The position of the concave portion faces the position of the second arcuate surface portion, and the curvature of the concave portion is smaller than the curvature of the second arcuate surface portion. The drive device according to claim 11, characterized in that.

13. The hole wall of the mounting hole includes a first inner wall, and the first inner wall faces the position of the first arcuate surface portion. The first inner wall is a straight wall parallel to the axis of the first shaft segment, or the first inner wall is an inclined wall inclined with respect to the axis of the first shaft segment, or the first inner wall is an arcuate concave wall. The drive device according to claim 12, characterized in that.

14. The mounting hole has a first hole portion and a second hole portion that communicate with each other. The aperture of the first hole portion is constant. Along the direction close to the first hole portion, the aperture of the second hole portion gradually decreases. The first shaft segment is provided to penetrate through the first hole portion and the second hole portion. The inflection point of the arcuate convex surface faces 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 arcuate convex surface contacts the hole wall of the first hole portion. The drive device according to claim 1, characterized in that.

15. 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 one end of the second shaft segment away from the first shaft segment. One end of the first shaft segment away from the second shaft segment is configured to be fixedly connected to the impeller. The housing assembly further has a position-limiting cavity and a through hole. The position-limiting cavity communicates with the mounting hole. The through hole communicates with the position-limiting cavity. The second shaft segment is rotatably accommodated in the position-limiting cavity. The third shaft segment is rotatably provided to penetrate through the through hole. The cross-sectional size of the second shaft segment is larger than the aperture of the mounting hole and the aperture of the through hole. The drive device according to claim 1, characterized in that.

16. The housing assembly further has a receiving cavity, the receiving cavity communicates with the through hole, the rotating shaft further has a fourth shaft segment connected to one end of the second shaft segment of the third shaft segment away from the second shaft segment, the fourth shaft segment is received in the receiving cavity, the fourth shaft segment is thinner than the third shaft segment, the driving device further includes a rotor and a stator received in the receiving cavity, the rotor is fixedly connected to the fourth shaft segment, the stator can drive the rotor to rotate, the rotor can drive the rotating shaft to rotate, and at least a part of the fourth shaft segment is received in the stator. The driving device according to claim 15, characterized in that.

17. The rotor has magnetism, 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 for driving the rotor to rotate, the first stator unit, the rotor and the second stator unit are sequentially provided along the axis of the fourth shaft segment, the fourth shaft segment is rotatably penetrated through the first stator unit, the rotor is fixedly connected to one end of the fourth shaft segment away from the third shaft segment, and the second stator unit and the rotating shaft are provided at intervals along the axis of the fourth shaft segment. Both the first stator unit and the second stator unit have a plurality of coil windings. The plurality of coil windings of the first stator unit are provided to surround the fourth shaft segment. The plurality of coil windings of the second stator unit are provided to surround 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 poles. The cross-sectional size of the magnetic poles of the second stator unit is larger than the cross-sectional size of the magnetic poles of the first stator unit. The driving device according to claim 16, characterized in that.

18. The housing assembly includes a separately provided pump housing, a shaft tube, a first shaft sleeve, and a second shaft sleeve. The pump housing has the accommodation cavity. One end of the shaft tube is fixedly connected to the pump housing. A support protrusion is provided at one end of the shaft tube close to the pump housing. One end of the shaft tube away from the pump housing has a mounting port. The first shaft sleeve and the second shaft sleeve are fixedly accommodated in the shaft tube from the mounting port and are provided along the axial direction of the shaft tube. The first shaft sleeve is closer to the impeller than the second shaft sleeve. The second shaft sleeve abuts against the support protrusion. The mounting hole is formed in the first shaft sleeve. The rotating shaft is rotatably penetrated through the first shaft sleeve and the second shaft sleeve. The driving device according to claim 16 is characterized by this.

19. Inner surface machining is formed on the hole wall at one end of the through hole close to the position limiting cavity. The driving device according to claim 15 is characterized by this.

20. A blood pump including an impeller and a driving device, wherein the driving device A housing assembly provided with a mounting hole A rotating shaft including a first shaft segment configured to be fixedly connected to the impeller and rotatably penetrated through the mounting hole. An arc-shaped convex surface is provided in the circumferential direction of the first shaft segment. At least a part of the arc-shaped convex surface is located in the mounting hole. The inflection point of the arc-shaped convex surface faces the hole wall of the mounting hole. At the inflection point of the arc-shaped convex surface, the gap between the arc-shaped convex surface and the hole wall of the mounting hole is the smallest. When the first shaft segment contacts the hole wall of the mounting hole, the inflection point of the arc-shaped convex surface includes a rotating shaft that contacts the hole wall of the mounting hole. The impeller is fixedly connected to the first shaft segment and is rotatable together with the rotating shaft. The blood pump is characterized by this.

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