An extracorporeal transmission device for an interventional blood pump

Abstract

The purpose of the present invention is to provide an extracorporeal transmission device for an interventional blood pump, comprising a rotating assembly and a driving assembly, wherein the driving assembly comprises a hollow cup coil, which sequentially controls the hollow cup coil to generate a rotating magnetic field, and the rotating magnetic field and the magnet of the rotating assembly act to drive the rotating assembly to rotate, and the distal end of the rotating shaft is fixed to the proximal end of the flexible transmission shaft, and the outer periphery of the rotating assembly and the flexible transmission shaft is provided with a sealed shell, and a liquid inlet interface and a liquid outlet interface are provided on the sealed shell, and a catheter is connected to the distal end of the sealed shell. In the above scheme, there is no rotor and active magnet inside the motor, and there is only one rotating component, the magnet, when working, which simplifies the design and avoids the operating vibration caused by the matching of various accessories. The flushing fluid will not contact the hollow cup coil at all, so the driving assembly can be reused, and only the sealed shell and the rotating assembly are disposable consumables, which greatly reduces the cost and enables more patients to benefit from it.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an extracorporeal transmission device of an interventional blood pump. Background Art

[0002] A percutaneously accessible ventricular assist device (VAD, hereinafter referred to as a blood pump) is a miniaturized blood pumping device that can be introduced into the heart and can be constructed to assist or replace natural heart function through circulating or continuous pumping of blood, providing hemodynamic support for cardiogenic shock and acute heart failure. At present, blood pumps use two technical routes. One is that the motor directly drives the impeller to pump blood, and the motor and impeller are inserted into the body when in use; the other is that the impeller is inserted into the body, the motor is located outside the body, and the torque of the motor is transmitted to the impeller through a flexible transmission shaft. For a blood pumping device with a motor located outside the body, an active magnet is usually connected to the motor shaft, and the flexible transmission shaft is connected to the driven magnet. The motor drives the active magnet to rotate, and the active magnet then drives the driven magnet to rotate to transmit the torque to the flexible transmission shaft. However, this structure has two disadvantages: one is that it involves many accessories and a complex structure; the other is that the structure of the motor plus the active magnet is prone to vibration, so it is also necessary to design a shock-absorbing structure and do dynamic balancing treatment, and the design is relatively complex. Summary of the invention

[0003] The object of the present invention is to provide an extracorporeal transmission device for an interventional blood pump which has a simple structure, a small volume and small vibration.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an extracorporeal transmission device of an interventional blood pump, including a rotating component and a driving component, the driving component including a hollow cup coil, which in turn controls the hollow cup coil to generate a rotating magnetic field, and the rotating magnetic field and the magnet of the rotating component drive the rotating component to rotate, the distal end of the rotating shaft is fixed to the proximal end of the flexible transmission shaft, and a sealed shell is arranged on the outer periphery of the rotating component and the flexible transmission shaft, and a liquid inlet interface and a liquid outlet interface are arranged on the sealed shell, and a catheter is connected to the distal end of the sealed shell.

[0005] Furthermore, the hollow cup coil is embedded in the potting glue and constitutes a potting coil, a magnetic constraint sleeve is arranged on the outer periphery of the potting coil, the hollow cup coil, the magnetic constraint sleeve and the rotating component are arranged coaxially, the axial length of the magnet is smaller than the axial length of the hollow cup coil and both ends of the magnet are located on the inner side of both ends of the hollow cup coil.

[0006] Furthermore, the proximal end of the hollow cup coil is welded to one side of the PCB board through a lead, and the other side of the PCB board is electrically connected to the controller through a lead.

[0007] Furthermore, the sealing shell includes a sealing sleeve arranged on the periphery of the magnet, the proximal end of the sealing sleeve is connected to the sealing cap, and the distal end is connected to the flushing seat, the two ends of the rotating shaft respectively protrude to the sealing cap and the inner cavity of the flushing seat, and form a rotational fit with the sealing cap and the inner wall of the flushing seat through the shaft sleeve, the liquid inlet interface and the liquid outlet interface are both arranged on the flushing seat, the outlet of the liquid inlet interface is communicated with the inner cavity of the flushing seat, and the inlet of the liquid outlet interface is communicated with the inner cavity of the sealing sleeve.

[0008] Furthermore, the hollow cup coil and the magnetic restraint sleeve are fixed into an integrated structure, and a slot is provided at the distal end face of the driving component. The pipe section of the liquid inlet interface or the liquid outlet interface is clamped in the slot to form axial and circumferential limit cooperation. The sealing sleeve, the sealing cap and the outer wall of the flushing seat are smoothly connected, and the outer diameter of the sealing shell formed is consistent with the inner diameter of the potting coil.

[0009] Furthermore, the flushing seat is a solid structure, and an internal thread is provided at the proximal end of the flushing seat. The internal thread and the external thread at the proximal end of the sealing sleeve form a threaded connection, and glue is injected into the thread to form a sealing fit. The flushing seat is provided with a through hole along its axial direction for the flexible transmission shaft and the rotating shaft to pass through. The liquid inlet interface is connected to the through hole, and the liquid outlet interface is connected to the inner cavity of the sealing sleeve through a channel opened inside the flushing seat, and the channel and the through hole are arranged to avoid each other.

[0010] Furthermore, the flexible transmission shaft is a hollow structure, the rotating shaft is a hollow shaft structure, the outer diameter of the flexible transmission shaft is equal to the outer diameter of the rotating shaft, the inner diameter of the flexible transmission shaft is equal to the inner diameter of the rotating shaft, the rotating shaft extends into the through hole of the flushing seat, the rotating shaft and the end of the flexible transmission shaft are abutted, and the outer peripheral sleeve of the connection is provided with a connecting sleeve, and the connecting sleeve, the rotating shaft and the flexible transmission shaft are welded and fixed.

[0011] Furthermore, the flexible transmission shaft is a double-layer hollow structure wound with alloy wire, and an outer layer is arranged on the periphery of the flexible transmission shaft. The flushing liquid enters the gap between the outer layer and the catheter from the liquid inlet interface and flows toward the distal side. Part of the flushing liquid flushes the blood pump bearing, and part of the flushing liquid returns from the inner cavity of the flexible transmission shaft to the inner cavity of the rotating shaft and enters the annular chamber between the rotating component and the sealing sleeve, and finally returns from the channel to the liquid outlet interface.

[0012] Furthermore, the liquid inlet interface is arranged near the distal side, the liquid outlet interface is arranged near the proximal side, the liquid inlet interface is connected to a liquid inlet pipe, the liquid outlet interface is connected to a liquid outlet pipe, and the liquid outlet interface pipe section is clamped in the clamping groove to form a limiting fit.

[0013] Furthermore, the transmission device also includes a shell, which is formed by two half bodies buckled together, and a placement groove that matches the shape of the drive component and the sealing shell is arranged in the shell.

[0014] In the above scheme, there is no rotor and active magnet inside the motor. When working, there is only one rotating part, the magnet, which simplifies the design and avoids the operation vibration caused by the matching of various accessories. The flushing fluid will not contact the hollow cup coil at all, so the drive component can be reused. Only the sealing shell and the rotating component are disposable consumables, which greatly reduces the cost and allows more patients to benefit from it. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is an outline diagram of an extracorporeal transmission device;

[0016] Figure 2 for Figure 1 Schematic diagram of the internal structure;

[0017] Figure 3 for Figure 1 A cross-sectional view of

[0018] Figure 4 The internal structure of the three-dimensional Figure 1 ;

[0019] Figure 5 The internal structure of the three-dimensional Figure 2 ;

[0020] Figure 6 It is a cross-sectional view of the internal structure;

[0021] Figure 7 for Figure 6 Schematic diagram of the structure after removing the drive components;

[0022] Figure 8 It is a structural schematic diagram of a sealed housing;

[0023] Fig. 9 It is a schematic diagram of the positional relationship among the rotating shaft, the flexible transmission shaft and the catheter;

[0024] Fig.10 Schematic diagram of the overall structure of the blood pump. DETAILED DESCRIPTION

[0025] For the sake of convenience, we first define the directions involved in the following text: "proximal" and "proximal side" refer to the side close to the operator / doctor, and "distal" and "distal side" refer to the side away from the operator / doctor, that is, the side close to the heart. Figure 1-10 The present invention is described in further detail.

[0026] See also Fig.10The blood pump here refers to a foldable impeller + extracorporeal transmission system. The extracorporeal drive mechanism transmits torque to the body through a flexible transmission shaft and drives the impeller to rotate to achieve the purpose of pumping blood. Since the drive mechanism does not need to be inserted through blood vessels, and the foldable impeller is inserted into the heart through blood vessels and is in a folded state when withdrawn, and is in an expanded state after the restriction ends after the intervention in the heart, the impeller has a large diameter, so at the same speed, the blood flow rate is large. The extracorporeal transmission device in this application is designed for this type of blood pump.

[0027] An extracorporeal transmission device for an interventional blood pump includes a rotating component 10 and a driving component 20. The driving component 20 includes a hollow cup coil 21, which controls the hollow cup coil 21 in turn to generate a rotating magnetic field. The rotating magnetic field acts on the magnet 11 of the rotating component 10 to drive the rotating component 10 to rotate. The distal end of the rotating shaft 12 is fixed to the proximal end of a flexible transmission shaft 30. A sealed shell 40 is arranged on the periphery of the rotating component 10 and the flexible transmission shaft 30. A liquid inlet interface 41 and a liquid outlet interface 42 are arranged on the sealed shell 40. A catheter 50 is connected to the distal end of the sealed shell 40.

[0028] In the above scheme, the hollow cup coil 21 is controlled by the controller to generate a rotating magnetic field. The rotating magnetic field interacts with the magnet 11 to drive the rotating shaft 12 to rotate stably, thereby driving the flexible transmission shaft 30 and the impeller to rotate. In the prior art, the motor is used to drive the active magnet to rotate, and the active magnet drives the driven magnet to rotate. The rotor inside the motor, the active magnet and the driven magnet are all in a rotating state. However, in the present application, there is no rotor inside the motor and the active magnet. When working, there is only one rotating component, the magnet 11, which simplifies the design and avoids the operating vibration caused by the matching of various accessories. The entire device has low vibration during operation and high reliability.

[0029] At the same time, the outer periphery of the rotating assembly 10 is sealed by the sealed shell 40, and the cleaning liquid enters the gap between the flexible transmission shaft 30 and the catheter 50 from the liquid inlet interface 41 and is transported to the distal end to cool the bearings on both sides of the impeller. The recovered flushing liquid returns to the proximal side from the hollow inner cavity of the flexible transmission shaft 30. On the one hand, it can recover the abrasives generated when the flexible transmission shaft 30 rotates, preventing the abrasives from entering the human body, and also lubricates the flexible transmission shaft 30. The flushing liquid can also cool and lubricate the rotating assembly 10 when it reaches the sealed shell 40, and finally the flushing liquid flows out from the liquid outlet interface 42. It can be seen from the flow path of the above-mentioned flushing liquid that the flushing liquid will not contact the hollow cup coil 21 at all, so the driving assembly 20 can be reused, and only the sealed shell 40 and the rotating assembly 10 are disposable consumables, which greatly reduces the cost of the blood pump and benefits more patients.

[0030] As a preferred embodiment of the present invention, the hollow cup coil 21 is embedded in the potting glue and constitutes a potting coil. A magnetic constraint sleeve 22 is arranged on the periphery of the potting coil. The hollow cup coil 21 and the magnetic constraint sleeve 22 are coaxially arranged with the rotating assembly 10. The axial length of the magnet 11 is smaller than the axial length of the hollow cup coil 21 and both ends of the magnet 11 are located inside the two ends of the hollow cup coil 21. During production, a hollow cup coil 21 slightly larger than the magnet 11 is first wound, and then the hollow cup coil 21 and the magnetic constraint sleeve 22 are placed in a mold, and a potting glue, such as epoxy resin, is injected into the mold cavity. During the curing process of the potting glue, the hollow cup coil 21 is embedded in the glue, and the hollow cup coil 21 and the magnetic constraint sleeve 22 are fixed to form an integrated drive assembly 20, which is convenient for the assembly and disassembly of the drive assembly 20 and the rotating assembly 10. The hollow cup coil 21 is potted with potting glue. After the glue is solidified, the hollow cup coil 21 is wrapped in the tubular glue. On the one hand, the potting coil has a fixed inner cavity, which can form an installation space for the sealed shell 40. On the other hand, the hollow cup coil 21 is completely wrapped in the tubular glue, thereby protecting the hollow cup coil 21 from damage. Because the drive assembly 20 (including the hollow cup coil 21) in the present application is reusable and can be assembled and disassembled with the sealed shell 40 on different blood pumps, the hollow cup coil 21 can be protected from damage during the whole process.

[0031] As mentioned above, after the hollow cup coil 21 is energized, it needs to be controlled by a controller to generate a stable rotating magnetic field to drive the magnet 11 to rotate stably. Therefore, the proximal end of the hollow cup coil 21 is welded to one side of the PCB board 23 through the lead 24, and the other side of the PCB board 23 is electrically connected to the controller through the lead 24. Figure 4 , Figure 5 As shown, the flexible transmission shaft 30 can be driven to rotate by using a controller to control the hollow cup coil 21 to generate a rotating magnetic field.

[0032] In order to prevent the leakage of flushing liquid, the sealing housing 40 includes a sealing sleeve 43 arranged on the outer periphery of the magnet 11, the proximal end of the sealing sleeve 43 is connected to the sealing cap 44, and the distal end is connected to the flushing seat 45, the two ends of the rotating shaft 12 protrude to the inner cavity of the sealing cap 44 and the flushing seat 45 respectively, and form a rotational fit with the sealing cap 44 and the inner wall of the flushing seat 45 through the shaft sleeve 46, the liquid inlet interface 41 and the liquid outlet interface 42 are both arranged on the flushing seat 45, the outlet of the liquid inlet interface 41 is communicated with the inner cavity of the flushing seat 45, and the inlet of the liquid outlet interface 42 is communicated with the inner cavity of the sealing sleeve 43. In order to facilitate the installation of various internal components, the sealing housing 40 is divided into three sections, namely the sealing sleeve 43 located in the middle, the sealing caps 44 and the flushing seat 45 located on both sides, and the three are connected by threads, and the threads are sealed with glue. At the same time, the sealing cap 44 and the flushing seat 45 are equivalent to bearing seats, which are used to support the two ends of the rotating shaft 12. The two ends of the rotating shaft 12 are sleeved with shaft sleeves 46. The shaft sleeves 46 are against the steps of the inner cavity of the sealing cap 44 and the flushing seat 45 to fix the axial and radial positions of the rotating shaft 21 and prevent the rotating shaft 21 from shifting during movement. On the other hand, the setting of the shaft sleeves 46 also has the function of reducing friction and vibration, thereby ensuring the smooth rotation of the rotating shaft 12.

[0033] In order to facilitate the installation and removal of the sealed housing 40, the hollow cup coil 21 and the magnetic restraint sleeve 22 are fixed as an integrated structure, and a slot 25 is provided at the distal end face of the driving assembly 20. The pipe section of the liquid inlet interface 41 or the liquid outlet interface 42 is clamped in the slot 25 to form an axial limit and a circumferential limit fit. The outer walls of the sealing sleeve 43, the sealing cap 44 and the flushing seat 45 are smoothly connected and the outer diameter of the sealed housing 40 formed is consistent with the inner diameter of the potting coil. After the rotating assembly 10 and the flexible transmission shaft 30 are installed in the sealed housing 40, the pipe section of the sealed housing 40 inserted from the distal end of the driving assembly 20 to the liquid inlet interface 41 or the liquid outlet interface 42 is clamped in the slot 25, that is, the assembly is realized. Due to the setting of the slot 25, the sealed housing 40 will not move axially, move radially or rotate circumferentially relative to the driving assembly 20 without external force. The positions of the two are reliable and the power transmission is stable. At this time, the relative position of the magnet 11 and the hollow cup coil 21 is also the best working position. The sealing housing 40 can be quickly disassembled by pulling it out from the far end of the driving assembly 20 , and the whole process is simple.

[0034] Furthermore, the flushing seat 45 is a solid structure, and the proximal end of the flushing seat 45 is provided with an internal thread, which is threadedly connected with the external thread at the proximal end of the sealing sleeve 43, and the glue is injected into the thread to form a sealing fit. The flushing seat 45 is provided with a through hole 451 along its axial direction for the flexible transmission shaft 30 and the rotating shaft 12 to pass through, the liquid inlet interface 41 is communicated with the through hole 451, and the liquid outlet interface 42 is communicated with the inner cavity of the sealing sleeve 43 through a channel 452 provided inside the flushing seat 45, and the channel 452 is arranged to avoid the through hole 451. Since the flushing liquid entering from the liquid inlet interface 41 is a relatively low-temperature, clean liquid, and the flushing liquid flowing out from the liquid outlet interface 42 is a high-temperature liquid mixed with impurities such as abrasives, the two cannot be mixed, otherwise the performance and service life of the blood pump will be affected.

[0035] In order to allow the flushing liquid to pass through both the proximal sleeve 46 and the distal sleeve 46, the flexible transmission shaft 30 is a hollow structure, the rotating shaft 12 is a hollow shaft structure, the outer diameter of the flexible transmission shaft 30 is equal to the outer diameter of the rotating shaft 12, the inner diameter of the flexible transmission shaft 30 is equal to the inner diameter of the rotating shaft 12, the rotating shaft 12 extends into the through hole 451 of the flushing seat 45, the ends of the rotating shaft 12 and the flexible transmission shaft 30 are butted, the outer periphery of the connection is provided with a connecting sleeve 32, and the connecting sleeve 32, the rotating shaft 12 and the flexible transmission shaft 30 are welded and fixed. The returned flushing liquid can enter the inner cavity of the rotating shaft 12 from the inner cavity of the flexible transmission shaft 30, and then cool and lubricate the sleeve 46 at the proximal end.

[0036] The flexible transmission shaft 30 is a double-layer hollow structure wound with alloy wire. An outer layer 31 is arranged on the periphery of the flexible transmission shaft 30. The flexible transmission shaft 30 wound with alloy wire will inevitably rub against the outer layer 31 during rotation, generating abrasives. The flushing liquid enters the gap between the outer layer 31 and the catheter 50 from the liquid inlet interface 41 and flows toward the distal side. Part of the flushing liquid flushes the blood pump bearing, and part of the flushing liquid returns from the inner cavity of the flexible transmission shaft 30 to the inner cavity of the rotating shaft 12 and enters the annular chamber between the rotating component 10 and the sealing sleeve 43, and finally returns to the liquid outlet interface 42 from the channel 452. After the returned flushing liquid reaches the proximal end of the flexible transmission shaft 30, the liquid is divided into two flows. One flow path directly enters the outside of the flexible transmission shaft 30 from the proximal end of the flexible transmission shaft 30 to flush the distal sleeve 46 and then enters the inner cavity of the sealing sleeve 43; the other flushing liquid enters the inner cavity of the rotating shaft 12 from the inner cavity of the flexible transmission shaft 30, and flows out from the proximal end of the rotating shaft 12, and then enters the inner cavity of the sealing sleeve 43 after flushing the proximal sleeve 46. The flushing liquid in the inner cavity of the sealing sleeve 43 finally flows out from the channel 452.

[0037] Furthermore, the liquid inlet interface 41 is arranged near the distal side, and the liquid outlet interface 42 is arranged near the proximal side. The liquid inlet interface 41 is connected to the liquid inlet pipe 41a, and the liquid outlet interface 42 is connected to the liquid outlet pipe 42a. The pipe section of the liquid outlet interface 42 is clamped in the clamping groove 25 to form a limit fit. In this way, the length of the channel 452 can be reduced, and the flushing liquid can flow out quickly while ensuring that the strength of the flushing seat 45 meets the requirements.

[0038] When in use, the transmission device also includes a housing 60, which is formed by buckling two halves, and the housing 60 is provided with a placement groove that matches the shape of the drive assembly 20 and the sealing shell 40. After the drive assembly 20 and the sealing shell 40 are assembled, the sealing shell 40 can be pulled out from the far end of the drive assembly 20 when subjected to external force. However, if the drive assembly 20 and the sealing shell 40 are placed in the placement groove of the housing 60, the degrees of freedom in all directions are limited, the relative position between the drive assembly 20 and the rotating assembly 10 is determined, and the power transmission is stable. It can also avoid the influence of the external environment on the hollow cup coil 21, and the housing 60 can also be used as a handle of the entire blood pump for the doctor to hold.

[0039] The embodiments described above are only some embodiments of the present application, rather than all embodiments. The preferred embodiments of the present application are given in the accompanying drawings, but they do not limit the patent scope of the present application. The present application can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Although the present application is described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific implementation methods, or to replace some of the technical features therein with equivalents. Any equivalent structure made using the contents of the specification and drawings of this application, directly or indirectly used in other related technical fields, is also within the scope of patent protection of this application.

Claims

1. An extracorporeal transmission device for an interventional blood pump, characterized in that: The invention comprises a rotating assembly (10) and a driving assembly (20), wherein the driving assembly (20) comprises a hollow cup coil (21), the hollow cup coil (21) is sleeved on the outer periphery of the rotating assembly (10) and the two are arranged coaxially, and the hollow cup coil (21) is sequentially controlled to generate a rotating magnetic field, and the rotating magnetic field acts on a magnet (11) of the rotating assembly (10) to drive the rotating assembly (10) to rotate, and the distal end of the rotating shaft (12) is fixed to the proximal end of the flexible transmission shaft (30), and the outer periphery of the rotating assembly (10) and the flexible transmission shaft (30) is provided with a sealing shell (40), and the sealing shell (40) is located at the rotating assembly (10). The rotating assembly (10) and the hollow cup coil (21) are separated, and a liquid inlet interface (41) and a liquid outlet interface (42) are provided on the sealing shell (40). A catheter (50) is connected to the distal end of the sealing shell (40). Cleaning liquid enters the gap between the flexible transmission shaft (30) and the catheter (50) from the liquid inlet interface (41) and is transported to the distal end to cool the bearings on both sides of the impeller. The recovered flushing liquid returns to the proximal side from the hollow inner cavity of the flexible transmission shaft (30) and the hollow inner cavity of the rotating shaft (12) and flows out from the liquid outlet interface (42).

2. The extracorporeal transmission device of the interventional blood pump according to claim 1, characterized in that: The hollow cup coil (21) is embedded in the potting glue and forms a potting coil. A magnetic constraint sleeve (22) is arranged on the outer periphery of the potting coil. The hollow cup coil (21), the magnetic constraint sleeve (22) and the rotating component (10) are coaxially arranged. The axial length of the magnet (11) is smaller than the axial length of the hollow cup coil (21), and both ends of the magnet (11) are located inside the two ends of the hollow cup coil (21).

3. The extracorporeal transmission device of the interventional blood pump according to claim 2, characterized in that: The proximal end of the hollow cup coil (21) is welded to one side of the PCB board (23) via a lead wire (24), and the other side of the PCB board (23) is electrically connected to the controller via the lead wire (24).

4. The extracorporeal transmission device of the interventional blood pump according to claim 1, characterized in that: The sealing housing (40) comprises a sealing sleeve (43) arranged on the outer periphery of the magnet (11); the proximal end of the sealing sleeve (43) is connected to the sealing cap (44) and the distal end is connected to the flushing seat (45); the two ends of the rotating shaft (12) respectively protrude into the inner cavities of the sealing cap (44) and the flushing seat (45), and are rotatably matched with the sealing cap (44) and the inner wall of the flushing seat (45) through the shaft sleeve (46); the liquid inlet interface (41) and the liquid outlet interface (42) are both arranged on the flushing seat (45); the outlet of the liquid inlet interface (41) is communicated with the inner cavity of the flushing seat (45), and the inlet of the liquid outlet interface (42) is communicated with the inner cavity of the sealing sleeve (43).

5. The extracorporeal transmission device of the interventional blood pump according to claim 4, characterized in that: The hollow cup coil (21) and the magnetic restraint sleeve (22) are fixed as an integrated structure, and a slot (25) is provided at the distal end surface of the driving assembly (20). A pipe section of the liquid inlet interface (41) or the liquid outlet interface (42) is clamped in the slot (25) to form an axial limit and a circumferential limit fit. The outer walls of the sealing sleeve (43), the sealing cap (44) and the flushing seat (45) are smoothly connected, and the outer diameter of the sealing housing (40) formed is consistent with the inner diameter of the potting coil.

6. The extracorporeal transmission device of the interventional blood pump according to claim 4, characterized in that: The flushing seat (45) is a solid structure. The proximal end of the flushing seat (45) is provided with an internal thread, which is threadedly connected with the external thread at the proximal end of the sealing sleeve (43), and the thread is sealed by injection of glue. The flushing seat (45) is provided with a through hole (451) along its axial direction for the flexible transmission shaft (30) and the rotating shaft (12) to pass through. The liquid inlet interface (41) is communicated with the through hole (451), and the liquid outlet interface (42) is communicated with the inner cavity of the sealing sleeve (43) through a channel (452) provided inside the flushing seat (45), and the channel (452) and the through hole (451) are arranged to avoid each other.

7. The extracorporeal transmission device of the interventional blood pump according to claim 6, characterized in that: The flexible transmission shaft (30) is a hollow structure, the rotating shaft (12) is a hollow shaft structure, the outer diameter of the flexible transmission shaft (30) is equal to the outer diameter of the rotating shaft (12), the inner diameter of the flexible transmission shaft (30) is equal to the inner diameter of the rotating shaft (12), the rotating shaft (12) extends into the through hole (451) of the flushing seat (45), the ends of the rotating shaft (12) and the flexible transmission shaft (30) are butted against each other, the outer periphery of the connection is provided with a connecting sleeve (32), and the connecting sleeve (32), the rotating shaft (12) and the flexible transmission shaft (30) are fixed by welding.

8. The extracorporeal transmission device of the interventional blood pump according to claim 6, characterized in that: The flexible transmission shaft (30) is a double-layer hollow structure formed by winding alloy wire. An outer layer (31) is arranged on the outer periphery of the flexible transmission shaft (30). Flushing liquid enters the gap between the outer layer (31) and the catheter (50) from the liquid inlet interface (41) and flows toward the distal side. Part of the flushing liquid flushes the blood pump bearing, and part of the flushing liquid returns from the inner cavity of the flexible transmission shaft (30) to the inner cavity of the rotating shaft (12) and enters the annular chamber between the rotating component (10) and the sealing sleeve (43), and finally returns to the liquid outlet interface (42) from the channel (452).

9. The extracorporeal transmission device of the interventional blood pump according to claim 5, characterized in that: The liquid inlet interface (41) is arranged near the distal side of the blood pump, and the liquid outlet interface (42) is arranged near the proximal side of the blood pump. The liquid inlet interface (41) is connected to a liquid inlet pipe (41a), and the liquid outlet interface (42) is connected to a liquid outlet pipe (42a). The pipe section of the liquid outlet interface (42) is clamped in the clamping groove (25) to form a limit fit.

10. The extracorporeal transmission device of the interventional blood pump according to claim 1, characterized in that: The transmission device further comprises a housing (60), the housing (60) comprising two half bodies buckled together, and a placement groove matching the shape of the drive assembly (20) and the sealing housing (40) is arranged in the housing (60).

Images