CN114082098A

CN114082098A - Flexible transmission system and blood pump

Info

Publication number: CN114082098A
Application number: CN202111242672.XA
Authority: CN
Inventors: 魏润杰; 胡雷俊; 刘星利
Original assignee: Zhejiang Diyuan Medical Equipment Co ltd
Current assignee: Zhejiang Diyuan Medical Equipment Co ltd
Priority date: 2021-10-25
Filing date: 2021-10-25
Publication date: 2022-02-25

Abstract

The embodiment of the application provides a flexible transmission system and a blood pump, wherein the flexible transmission system comprises a flexible shaft, a guide pipe, a hard shaft arranged at the far end of the flexible shaft and a first bearing assembly arranged in the guide pipe, and the flexible shaft is arranged in the guide pipe; the near end of the hard shaft is positioned in the guide pipe, and the far end of the hard shaft is used for being connected with an impeller of the pump body; the hard shaft is rotatably supported on the first bearing assembly. In the embodiment of the application, the hard shaft is additionally arranged between the impeller and the flexible shaft, the hard shaft transmits torque to the impeller, and the first bearing assembly supports the hard shaft, so that the other side of the impeller in the axial direction does not need to be provided with another bearing, and the rotating coaxiality of the impeller can be guaranteed; the scheme of transmitting torque by adopting the flexible shaft does not need to arrange a bearing in the related technology in the pump body under the condition of ensuring the rotating coaxiality of the impeller.

Description

Flexible transmission system and blood pump

Technical Field

The application relates to the technical field of medical equipment, in particular to a flexible transmission system and a blood pump.

Background

The blood pump device is generally used for promoting the normal circulation of blood of a medical object in an operation, namely, one end of the blood pump device, provided with a blood pump, is inserted into a ventricle of the medical object, the other end of the blood pump device is inserted into an artery of a heart, and the blood in the ventricle of the heart is pumped into the artery of the medical object through the operation of the blood pump, so that the normal blood circulation of the medical object is ensured, and the blood of the medical object can still normally circulate when the heart-related operation is performed on the medical object.

In some related art, the external motor and the pump body of the blood pump device are placed in the patient, but the possible effects include: the external motor has the use risk of the system in the internal environment of the patient; elements such as an internal coil, a rotor and a magnet of the external motor have the risk of particle precipitation; the structure of the external motor limits the size reduction of the part implanted into the human body.

Therefore, some blood pump devices in the related art adopt a mode of externally arranging a motor, and connect an impeller and a motor shaft through a flexible shaft. However, this method has poor coaxiality of the impeller.

Disclosure of Invention

In view of the above, it is desirable to provide a flexible transmission system and a blood pump for improving the coaxiality of impellers.

The embodiment of the present application provides a flexible transmission system of blood pump, includes:

the flexible shaft is used for receiving torque input by the external motor;

a catheter, the flexible shaft disposed within the catheter;

the hard shaft is arranged at the far end of the flexible shaft, the near end of the hard shaft is positioned in the guide pipe, and the far end of the hard shaft is used for being connected with an impeller of the pump body;

a first bearing assembly disposed within the conduit, the hard shaft being rotatably supported on the first bearing assembly.

In some embodiments, the first bearing assembly comprises a bearing support and a plurality of first bearings disposed within the bearing support, each of the first bearings being coaxially disposed, the hard shaft passing through each of the first bearings in turn, the periphery of the bearing support abutting the inner wall of the conduit.

In some embodiments, the flexible drive system includes a first coupling, and the flexible shaft and the hard shaft are connected by the first coupling.

In some embodiments, the flexible drive system includes a sleeve nestingly disposed within the conduit and nested over the flexible shaft, the outer wall of the flexible shaft and the inner wall of the sleeve defining a first channel therebetween for containing a liquid medium.

In some embodiments, a liquid medium is encapsulated within the first channel.

In some embodiments, the outer wall of the sleeve and the inner wall of the conduit define a second channel therebetween for containing a liquid medium;

a liquid medium is encapsulated in the second cavity; or the near end of the flexible transmission system is provided with a filling inlet communicated with the first cavity and a filling outlet communicated with the second cavity, the far end of the first cavity is communicated with the far end of the second cavity, the second cavity is positioned at the downstream of the first cavity along the flowing direction of the liquid medium, and the flowing directions of the liquid medium in the first cavity and the second cavity are opposite.

In some embodiments, the outer wall of the sleeve is provided with a protrusion by which the sleeve abuts the inner wall of the catheter.

In some embodiments, the projection comprises a helical structure extending helically along the axis of the sleeve.

In some embodiments, the circumferential surface of the flexible shaft has a helical winding configured to urge the liquid medium in the first channel toward the distal end of the first channel during rotation of the flexible shaft.

In some embodiments, the flexible transmission system includes a fixing frame, the proximal end of the flexible shaft at least partially penetrates through the fixing frame, a first mounting groove is disposed on a first axial side of the fixing frame, and both the proximal end of the catheter and the proximal end of the cannula are fixed in the first mounting groove.

In some embodiments, the proximal end of the flexible shaft extends out of the fixed mount, a second mounting groove is disposed on a second axial side of the fixed mount, the flexible drive train includes a second bearing, the first bearing assembly is disposed in the second mounting groove, and the proximal end of the flexible shaft is supported on the second bearing.

An embodiment of the present application provides a blood pump, including:

the pump body comprises a pump shell and an impeller arranged in the pump shell;

an external motor;

and the flexible transmission system of any embodiment of the present application, wherein the external motor inputs torque to the flexible shaft.

In the embodiment of the application, the hard shaft is additionally arranged between the impeller and the flexible shaft, the hard shaft transmits torque to the impeller, and the first bearing assembly supports the hard shaft; the other axial side of the impeller does not need to be provided with another bearing, and the rotating coaxiality of the impeller can be guaranteed.

The blood pump of the embodiment of the application adopts the scheme that the flexible shaft transmits the torque, and under the condition that the rotating coaxiality of the impeller is guaranteed, bearings in the related technology do not need to be arranged in the pump body, so that the wire threading operation of the guide wire is facilitated, the wire threading time is reduced, and the operation time is saved.

Drawings

FIG. 1 is a schematic structural view of a blood pump according to a first embodiment of the present disclosure after passing through a guidewire;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

FIG. 3 is a schematic view of another embodiment of the pump outlet at A in FIG. 1;

FIG. 4 is a schematic structural diagram of a flexible drive system according to an embodiment of the present application;

FIG. 5 is a schematic structural view of a blood pump according to a second embodiment of the present application;

FIG. 6 is a schematic structural view of a blood pump according to a third embodiment of the present application;

FIG. 7 is an enlarged partial schematic view at C of FIG. 6;

FIG. 8 is a schematic structural diagram of an impeller according to an embodiment of the present application;

FIG. 9 is a schematic structural view of an impeller according to another embodiment of the present application;

FIG. 10 is a schematic structural view of a cannula according to an embodiment of the present application;

FIG. 11 is a schematic structural view of a cannula according to another embodiment of the present application;

FIG. 12 is a schematic structural view of a flexible shaft according to an embodiment of the present application;

FIG. 13 is a schematic view of a flexible shaft according to another embodiment of the present application.

Description of the reference numerals

A blood pump 100;

a pump body 1; a pump housing 11; an impeller 12; a pump inlet 11 a; a pump outlet 11 b;

a flexible transmission system 2; a flexible shaft 21; a spirally wound structure 21 a; a hard shaft 22; a sleeve 23; the projections 231; a conduit 24; a first channel 2 a; a second channel 2 b;

a first bearing assembly 25; a first bearing 251; a bearing support 252;

a mount 26; the shaft hole 26 a; the first mounting groove 26 b; a second mounting groove 26 c; a filling opening 26 d; a perfusion outlet 26 f;

a first coupling 27; a second bearing 28;

an external motor 4; a motor shaft 41;

a second coupling 5;

a flexible protective tube 6;

guide wire 300

Detailed Description

Embodiments of the present application will be described in further detail below with reference to the drawings and examples. The following examples are intended to illustrate the present application but are not intended to limit the scope of the present application.

In the description of the embodiments of the present application, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the embodiments of the present application, "distal end" and "proximal end" refer to orientations.

The embodiment of the present application provides a blood pump 100, please refer to fig. 1, 5 and 6, which includes a pump body 1, a flexible transmission system 2 and an external motor 4.

It should be noted that the flexible transmission system 2 is a slender flexible structure, and the flexible transmission system 2 and the pump body 1 are placed in the body of the patient; the external motor 4 can not be put into the patient, but is located outside the patient, avoids the external motor 4 to put into the patient and risk that brings, in addition, aspects such as the shape, the size of external motor 4 need not to receive the restriction of blood vessel, designs and arranges more in a flexible way.

Referring to fig. 1, 5 and 6, the pump body 1 includes a pump casing 11 and an impeller 12 disposed in the pump casing 11. The pump housing 11 is provided with a pump inlet 11a and a pump outlet 11b, the pump outlet 11b being located on the side of the proximal end of the impeller 12, and the pump inlet 11a being located on the side of the distal end of the impeller 12, that is, the pump outlet 11b and the pump inlet 11a being located on axially opposite sides of the impeller 12.

When the impeller 12 rotates, blood in the heart chamber is drawn into the pump housing 11 from the pump inlet 11a, and the impeller 12 drives the blood out of the pump outlet 11 b.

The type of impeller 12 is not limited, for example, referring to fig. 8, in some embodiments, the impeller 12 may be an axial flow impeller; referring to fig. 9, in other embodiments, the impeller 12 may be a mixed-flow impeller or the like.

Referring to fig. 1, 5 and 6, a flexible protection tube 6 is disposed at a distal end of the pump body 1, and the flexible protection tube 6 can be bent moderately.

Referring to fig. 1, the flexible protective tube 6 has a passage therein for passing a guide wire 300 therethrough. During installation, the guide wire 300 penetrates into the flexible protection tube 6 from the distal end of the flexible protection tube 6, penetrates through the flexible protection tube 6 from the inside, penetrates out to the inside of the pump housing 11 from the proximal end of the flexible protection tube 6, and the guide wire 300 penetrates through the pump housing 11 along the axial direction of the pump housing 11 and penetrates out from the pump outlet 11 b.

The blood pump 100 is moved along a blood vessel to a target location within a patient under guidance of the guidewire 300.

It should be noted that after the blood pump 100 is placed at the target location within the patient, the guide wire 300 is withdrawn.

Referring to fig. 1, 4, 5 and 6, the flexible transmission system 2 includes a guide tube 24, a flexible shaft 21, and a hard shaft 22 disposed at a distal end of the flexible shaft 21, wherein the flexible shaft 21 is disposed in the guide tube 24.

The catheter 24 is a flexible catheter, and can be bent and deformed together with the flexible shaft 21 to adapt to the vascular structure of the human body. The catheter 24 is in contact with the internal environment of the patient and the flexible shaft 21 is not in contact with the internal environment of the patient.

The external motor 4 is used to input torque to the flexible shaft 21.

The proximal end of the hard shaft 22 is located in the guide tube 24, and the distal end of the hard shaft 22 is used for connection with the impeller of the pump body 1, that is, the distal end of the hard shaft 22 extends into the pump housing 11 and is connected with the impeller 12, and the hard shaft 22 is used for transmitting the torque of the flexible shaft 21 to the impeller 12.

It should be noted that the rigid shaft 22 refers to a shaft having a certain rigidity and will not follow the flexible shaft 21 to bend during the insertion into the patient, for example, a metal shaft.

In order to ensure the concentricity of rotation of the impeller 12, the blood pump 100 of the embodiment of the present application further includes a first bearing assembly 25 disposed within the conduit 24, the hard shaft 22 being rotatably supported on the first bearing assembly 25. That is, the first bearing assembly 25 does not extend into the pump housing 11 and occupy space within the pump housing 11.

In the related technology, the soft shaft penetrates through the impeller from the center of the impeller, bearings are required to be arranged at two axially opposite ends of the impeller, and the soft shaft parts at the two ends of the impeller are supported on the bearings. On one hand, although the bearing is arranged, the flexible shaft has flexibility, and the coaxiality of the impeller cannot be ensured in the rotating process of the impeller; on the other hand, the bearing is arranged in the pump body, when the guide wire penetrates through the pump shell, the guide wire needs to penetrate through the bearing in the pump shell, the bearing is not beneficial to wire penetrating operation of the guide wire, time and labor are wasted, the operation time can be prolonged, and the operation risk of a patient is increased.

In the embodiment of the present application, the hard shaft 22 is additionally arranged between the impeller 12 and the flexible shaft 21, the hard shaft 22 transmits torque to the impeller 12, and the first bearing assembly 25 supports the hard shaft 22, and the hard shaft 22 has good rigidity, so that the impeller 12 has good coaxiality due to the cooperation of the hard shaft 22 and the first bearing assembly 25, and the other axial side of the impeller 12 does not need to be provided with another bearing, and the coaxiality of the rotation of the impeller 12 can be ensured.

The blood pump of the embodiment of the application adopts the scheme that the flexible shaft 21 transmits the torque, and under the condition that the rotating coaxiality of the impeller 12 is guaranteed, bearings in the related technology do not need to be arranged in the pump body 11, so that the wire threading operation of the guide wire 300 is facilitated, the wire threading time is reduced, and the operation time is saved.

The specific configuration of the pump housing 11 is not limited.

Illustratively, in some embodiments, the pump casing 11 includes a collapsible frame that supports the membrane and forms a pump chamber, and a membrane that overlies the collapsible frame, and the impeller 12 is disposed within the pump chamber. The collapsible stent provides structural support for the cover. In this embodiment, the pump housing 11 is collapsible, and when delivered in a blood vessel, the pump housing 11 collapses to a smaller size, and when the pump body 1 reaches the ventricle, the pump housing 11 expands and becomes larger in size.

In other embodiments, the pump housing 11 is of a non-collapsible construction, e.g., the pump housing 11 is relatively stiff and the pump housing 11 remains the same size and configuration throughout.

For example, referring to fig. 2 and 3, the edge of the pump outlet 11b has a chamfer or fillet, which reduces the risk of the guide wire 300 bending or wearing at the edge of the pump outlet 11 b.

It will be appreciated that in some embodiments, at least a portion of the structure of the impeller 12 and the hard shaft 22 may be an integrally formed structure; in other embodiments, the impeller 12 and the hard shaft 22 may be a separate structure and connected together, which is not limited herein.

The specific structure of the first bearing assembly 25 is not limited.

Referring to fig. 1, the first bearing assembly 25 includes a bearing support 252 and a plurality of first bearings 251 disposed in the bearing support 252, each first bearing 251 is disposed coaxially, the hard shaft 22 sequentially passes through each first bearing 251, and the periphery of the bearing support 252 abuts against the inner wall of the guide tube 24.

In the embodiments of the present application, "a plurality" means at least two.

In this embodiment, the bearing support 252 provides a mounting position for each first bearing 251, so as to facilitate uniform positioning and mounting of each first bearing 251. Because a plurality of first bearings 251 are adopted, each first bearing 251 defines a determined axis, and the rotation center line of the hard shaft 22 is coincident with the axis, so that the coaxiality of the hard shaft 22 can be further improved, and the deflection probability of the hard shaft 22 is reduced.

It should be noted that the first bearing 251 may be a standard component available on the market.

The type of the first bearing 251 is not limited, and may be, for example, a radial sliding bearing, a rolling bearing, an axial sliding bearing, or the like, without being limited thereto.

The bearing support 252 acts as a rigid structure that supports the distal end of the catheter 24, serving as a location for the distal end of the catheter 24.

The connection between the flexible shaft 21 and the rigid shaft 22 is not limited.

Referring to fig. 5, for example, in some embodiments, the flexible shaft 21 and the hard shaft 22 are directly connected together by welding or the like.

Referring to fig. 1, 4 and 6, in other embodiments, the flexible transmission system 2 includes a first coupling 27, and the flexible shaft 21 and the hard shaft 22 are connected by the first coupling 27. In this embodiment, the flexible shaft 21 serves as a driving shaft, the hard shaft 22 serves as a driven shaft, and the first coupling 27 couples the two shafts to rotate together and transmit torque.

The specific structure of the first coupling 27 is not limited, and for example, a standard component known in the art can be used.

Illustratively, in some embodiments, referring to fig. 1, 4, 5, and 6, the flexible transmission system 2 includes a sleeve 23, the sleeve 23 is nested in the guide tube 24 and is nested on the flexible shaft 21, that is, in a radial outward direction, the sleeve 23 and the guide tube 24 are nested in sequence on a radial outer side of the flexible shaft 21, the guide tube 24 is nested outside the sleeve 23, and the sleeve 23 is not in contact with the internal environment of the patient.

Illustratively, referring to fig. 1, 4, 5 and 6, a first channel 2a for containing a liquid medium is defined between the outer wall of the flexible shaft 21 and the inner wall of the sleeve 23, and the first channel 2a is not communicated with the pump chamber. That is, the liquid medium in the first channel 2a does not enter the pump chamber, and the blood in the pump chamber does not enter the first channel 2 a.

It should be noted that the length of the first channel 2a is approximately the length of the sleeve 23.

The liquid medium in the first cavity 2a can reduce the friction between the flexible shaft 21 and the inner wall of the sleeve 23, reduce the vibration caused by the high-speed rotation of the flexible shaft 21, and play a role in heat dissipation, temperature reduction and lubrication of the flexible shaft 21.

The liquid medium may be a biocompatible liquid, such as physiological saline, glucose solution, or the like.

Referring to fig. 1, 4, 5 and 6, a second channel 2b is defined between the outer wall of the sleeve 23 and the inner wall of the conduit 24. The second channel 2b is not communicated with the pump cavity. That is, the liquid medium in the second chamber 2b does not enter the pump chamber, and the blood in the pump chamber does not enter the second chamber 2 b.

The liquid in the second cavity 2b contacts with the outer wall of the sleeve 23, so that the heat of the sleeve 23 is absorbed, the temperature of the sleeve 23 is reduced, the heat transferred from the sleeve 23 to the flexible shaft 21 and the liquid medium in the first cavity 2a can be reduced, and the temperature of the flexible shaft 21 can be reduced.

It should be noted that the blood pump 100 needs to be placed into the heart through a blood vessel of the human body, and therefore, the outer diameter of the catheter 24 is limited. In the related art, a narrow cavity needs to be machined in the wall of the guide tube 24, and the guide tube 24 has a small size, high machining difficulty and high process requirement.

In the embodiment of the application, the first cavity 2a and the second cavity 2b are formed by nesting the sleeve 23 and the guide pipe 24, and the sleeve 23 can both use relatively thin pipe walls, so that the structure is simple, the processing and manufacturing requirements are reduced, and the manufacturing is facilitated.

It should be noted that, at least during operation of the blood pump 100, the first and

second channels

2a, 2b contain a liquid medium.

Illustratively, in some embodiments, a liquid medium is encapsulated within both the first channel 2a and the second channel 2 b. That is, the liquid medium in both the first channel 2a and the second channel 2b is not exchanged with the extracorporeal environment. The liquid medium is sealed in the first and

second channels

2a and 2 b. In this embodiment, the first channel 2a and the second channel 2b are not communicated with each other, or are communicated with each other.

In the embodiment where the first channel 2a and the second channel 2b do not communicate with each other, the liquid medium sealed in the first channel 2a and the liquid medium sealed in the second channel 2b may be the same, or may be different.

In other exemplary embodiments, referring to fig. 7, the proximal end of the flexible transmission system 2 is provided with an infusion inlet 26d communicating with the first channel 2a and an infusion outlet 26f communicating with the second channel 2b, that is, the infusion inlet 26d and the infusion outlet 26f are both located at the proximal end of the flexible transmission system 2.

The distal end of the first channel 2a communicates with the distal end of the second channel 2b, the second channel 2b is located downstream of the first channel 2a in the direction of flow of the liquid medium, and the liquid medium in the first channel 2a and the second channel 2b flows in opposite directions. That is, the first channel 2a and the second channel 2b form a passage in the liquid flow direction.

In this embodiment, the liquid medium in the first channel 2a and the liquid medium in the second channel 2b are in a dynamic flow state. During the use of the blood pump 100, the external liquid medium is infused into the first lumen 2a from the infusion inlet 26d, flows from the proximal end to the distal end of the first lumen 2a, enters the second lumen 2b, flows from the distal end to the proximal end of the second lumen 2b, and is finally discharged from the infusion outlet 26 f. The flowing liquid medium can drive the heat generated by the flexible shaft 21 in time, and the heat dissipation and cooling effects on the flexible shaft 21 are improved.

It should be noted that the way of communicating the distal end of the first channel 2a with the distal end of the second channel 2b is not limited, for example, in some embodiments, the distal end of the second channel 2b is opened to form a port, and the liquid medium of the first channel 2a enters the second channel 2b from the port of the second channel 2 b. In other embodiments, the wall of the distal end of the cannula 23 is provided with an overflowing hole through which the first lumen 2a and the second lumen 2b communicate.

The flexible shaft 21 is not limited in configuration as long as the flexible shaft 21 can transmit torque conveniently and has bending performance. For example, referring to FIG. 12, in some embodiments, flexible shaft 21 is braided using a plurality of braided strands. For another example, referring to fig. 13, in other embodiments, the flexible shaft 21 is a metal spring.

It should be noted that the rotation direction of the flexible shaft 21 is consistent with the rotation direction when the flexible shaft transmits the torque, so that the structure of the flexible shaft 21 does not become loose during the rotation of the flexible shaft 21.

Referring to fig. 12 and 13, for example, a spiral winding structure 21a is disposed on the circumferential surface of the flexible shaft 21. for example, referring to fig. 12, in the embodiment where the flexible shaft 21 is woven by using a plurality of braided strands, the spiral line formed after weaving is the spiral winding structure 21 a. For another example, referring to fig. 13, in the embodiment that the flexible shaft 21 is a metal spring, the helical winding of the metal spring itself is the above-mentioned helical winding structure.

During rotation of the flexible shaft 21, the spiral wound structure 21a is able to force the liquid medium in the first lumen towards the distal end of the first channel 2 a. The flexible shaft 21 can promote the flow of liquid medium through spiral winding structure 21a in the rotation process, accelerate liquid exchange speed, promote heat dissipation cooling effect.

Illustratively, the outer wall of the sleeve 23 is provided with a projection 231, and the sleeve 23 abuts against the inner wall of the conduit 24 through the projection 231. On one hand, the protrusion 231 can ensure the position of the sleeve 23 in the guide pipe 24, reduce the contact area between the sleeve 23 and the guide pipe 24, reduce the friction resistance of the guide pipe 24 during the process of sleeving the sleeve 23 on the sleeve 23, and on the other hand, make the sleeve 23 have substantially no radial play clearance, thereby reducing the radial swing of the flexible shaft 21; on the other hand, it is also convenient to form the second channel 2b described above.

The structural shape of the projection 231 is not limited. For example, in some embodiments, the projection 231 includes a helical structure that extends helically along the axial direction of the sleeve 23. It will be appreciated that in some embodiments, referring to fig. 10, the helical formation may extend continuously from the proximal end of the sleeve 23 to the distal end of the sleeve 23. In other embodiments, referring to FIG. 11, only a portion of the length of the sleeve 23 is provided with a helical structure.

The helical structure can increase the contact area of the sleeve 23 and the liquid medium, namely, the heat dissipation area, and improve the heat dissipation effect.

A spiral groove is formed on the radial inner side of the spiral structure; the spiral direction of the spiral groove is the same as the spiral winding structure 21 a. During rotation of the flexible shaft 21, the spiral wound structure 21a has the effect of pumping the liquid medium from the proximal end to the distal end, and the liquid medium will follow the spiral groove, thus reducing the flow resistance.

Referring to fig. 1, 4, 5, 6 and 7, the flexible transmission system 2 includes a fixed frame 26, and the proximal end of the flexible shaft 21 is at least partially inserted into the fixed frame 26. The fixing frame 26 supports and positions the proximal end of the flexible shaft 21. Specifically, the fixing bracket 26 is provided with a shaft hole 26a penetrating the fixing bracket 26 in the longitudinal direction of the flexible shaft 21, and the flexible shaft 21 is rotatably inserted through the shaft hole 26 a.

It is understood that the proximal end of the flexible shaft 21 may be embedded in the holder 26 or may pass through the holder 26.

Referring to fig. 7, a first mounting groove 26b is formed on a first axial side of the mounting bracket 26, and the proximal end of the catheter 24 and the proximal end of the cannula 23 are fixed in the first mounting groove 26 b. That is, the flexible shaft 21 passes through the first mounting groove 26 b. And neither the guide tube 24 nor the sleeve 23 extends into the shaft hole 26 a.

Illustratively, the proximal end of the guide tube 24 and the proximal end of the sleeve 23 are each abutted against the groove bottom wall of the first mounting groove 26b, thus facilitating positioning of the proximal ends of the guide tube 24 and the sleeve 23.

In the embodiment where the perfusion inlet 26d and the perfusion outlet 26f are provided, the perfusion inlet 26d and the perfusion outlet 26f are provided on the fixing frame 26. The port of the fill port 26d is disposed on the slot bottom wall of the first mounting slot 26b and is aligned with the space between the proximal end of the cannula 23 and the flexible shaft 21. The port of the irrigation outlet 26f is provided on the tank bottom wall of the first mounting groove 26b, and is aligned with the gap between the proximal end of the sleeve 23 and the catheter 24.

Illustratively, the proximal end of the flexible shaft 21 passes through the fixing frame 26, and a second mounting groove 26c is disposed on a second axial side of the fixing frame 26, through which the flexible shaft 21 passes.

The flexible drive system 2 includes a second bearing 28, the first bearing assembly 25 is disposed in the second mounting slot 26c, and the proximal end of the flexible shaft 21 is supported on the second bearing 28.

It should be noted that, in some embodiments, referring to fig. 5, the flexible shaft 21 and the motor shaft 41 of the external motor 4 may be directly connected together by welding or the like.

In other embodiments, referring to fig. 1 and 6, the blood pump 100 includes a second coupling 5, and the motor shaft 41 of the external motor 4 is connected to the flexible shaft 21 through the second coupling 5.

In the description of the present application, reference to the description of the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the embodiments of the present application. In this application, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Moreover, various embodiments or examples and features of different embodiments or examples described herein may be combined by one skilled in the art without contradiction.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A flexible drive system for a blood pump, comprising:

the flexible shaft (21) is used for receiving the torque input by the external motor (4);

a conduit (24), the flexible shaft (21) being disposed within the conduit (24);

a hard shaft (22) arranged at the far end of the flexible shaft (21), the near end of the hard shaft (22) is positioned in the guide pipe (24), and the far end of the hard shaft (22) is used for being connected with an impeller (12) of the pump body (1);

a first bearing assembly (25) disposed within the guide tube (24), the hard shaft (22) being rotatably supported on the first bearing assembly (25).

2. The flexible drive system of claim 1, wherein the first bearing assembly (25) comprises a bearing support (252) and a plurality of first bearings (251) disposed within the bearing support (252), each of the first bearings (251) being coaxially disposed, the hard shaft (22) passing through each of the first bearings (251) in turn, a periphery of the bearing support (252) abutting an inner wall of the guide tube (24).

3. The flexible drive system of claim 1, comprising a first coupling (27), wherein the flexible shaft (21) and the hard shaft (22) are connected by the first coupling (27).

4. The flexible transmission system according to claim 1, characterized in that it comprises a sleeve (23), said sleeve (23) being arranged nested inside said guide tube (24) and on said flexible shaft (21), a first channel (2a) for containing a liquid medium being defined between the outer wall of said flexible shaft (21) and the inner wall of said sleeve (23).

5. The flexible drive system according to claim 4, characterized in that a liquid medium is enclosed in the first channel (2 a).

6. The flexible transmission system according to claim 4, characterized in that a second chamber (2b) for containing a liquid medium is defined between the outer wall of the sleeve (23) and the inner wall of the conduit (24);

a liquid medium is enclosed in the second chamber (2 b); or the near end of the flexible transmission system is provided with a perfusion inlet (26d) communicated with the first cavity (2a) and a perfusion outlet (26f) communicated with the second cavity (2b), the far end of the first cavity (2a) is communicated with the far end of the second cavity (2b), the second cavity (2b) is positioned at the downstream of the first cavity (2a) along the flow direction of the liquid medium, and the flow directions of the liquid medium in the first cavity (2a) and the second cavity (2b) are opposite.

7. The flexible transmission system according to claim 4, characterized in that the outer wall of the sleeve (23) is provided with a protrusion (231), the sleeve (23) abutting with the inner wall of the conduit (24) through the protrusion (231).

8. The flexible drive system of claim 7, wherein the projection (231) comprises a helical structure extending helically in an axial direction of the sleeve (23).

9. The flexible transmission system according to claim 4, wherein the circumferential surface of the flexible shaft (21) has a helical winding (21a), the helical winding (21a) being capable of pushing the liquid medium in the first channel (2a) towards the distal end of the first channel (2a) during rotation of the flexible shaft (21).

10. The flexible transmission system according to claim 1, characterized in that the flexible transmission system comprises a fixed frame (26), the proximal end of the flexible shaft (21) is at least partially inserted into the fixed frame (26), a first installation groove (26b) is arranged on a first axial side of the fixed frame (26), and the proximal end of the catheter (24) and the proximal end of the sleeve (23) are both fixed in the first installation groove (26 b).

11. The flexible drive system of claim 10, wherein a proximal end of the flexible shaft (21) passes out of the mounting bracket (26), an axially second side of the mounting bracket (26) is provided with a second mounting slot (26c), the flexible drive system comprising a second bearing (28), the first bearing assembly (25) being disposed in the second mounting slot (26c), the proximal end of the flexible shaft (21) being supported on the second bearing (28).

12. A blood pump, comprising:

the pump body (1), the pump body (1) comprises a pump shell (11) and an impeller (12) arranged in the pump shell (11);

an external motor (4);

and a flexible drive system according to any one of claims 1 to 11, the external electrical machine (4) inputting torque to the flexible shaft (21).