Interventional fluid pumping device

Abstract

The invention provides an intrusive fluid pumping device. The intrusive fluid pumping device comprises a body, a sheathing canal and a sheathing canal connecting unit. The far end of the sheathing canal connecting unit covers the near end of the body; a hollow inner cavity is formed in the sheathing canal connecting unit, and the far end of the sheathing canal is arranged in the hollow inner cavity. According to the fluid pumping device, the sheath tube and the body of the fluid pumping device are connected through the independent sheath tube connecting unit, elements in the sheath tube connecting unit are separated from blood, the situation that the blood corrodes elements and bonding materials in the pumping system is avoided, and the problems that potential safety hazards are caused by corrosion, the connecting strength is reduced and the like are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical instruments, and in particular to an interventional fluid pumping device. Background Art

[0002] In the prior art, when the patient's heart function weakens and the blood pumping capacity is insufficient, a ventricular assist device is often needed to assist the heart in pumping blood, so as to pump the blood in the heart through the blood pumping device, and guide the blood to the aorta outside the heart and flow to the whole body. The ventricular assist device mainly consists of two parts: a catheter and a blood pumping device. The blood pumping device is arranged at the distal end of the catheter (i.e., the end away from the operator or physician). The catheter is inserted through the femoral artery, axillary artery or carotid artery, and the blood pumping device passes through the aorta. Its suction channel is inserted into the left ventricle of the patient's heart across the valve, and its outflow channel is in the aorta. In this way, the impeller of the blood pumping device rotates to pump the left ventricular blood to the aorta through the suction channel. Of course, the blood pumping device can also be inserted into the right ventricle of the patient's heart through veins such as the femoral vein by means of a catheter, and the right ventricular blood is pumped to the pulmonary artery. In the prior art, the sheath assembly and the blood pumping device are fixedly connected only by a coating method such as injection molding or gluing. The injection molding and adhesive materials are exposed to the environment over a large area. For example, in an interventional state, blood directly contacts the injection molding or adhesive coating materials over a large area. The weak alkalinity of the blood will gradually corrode the injection molding or adhesive materials, causing the connection strength of the sheath assembly to decrease, and even causing safety hazards such as disconnection, resulting in low reliability of the equipment. Summary of the invention

[0003] In order to overcome at least one of the problems in the related art, the present invention provides an intrusive fluid pumping device.

[0004] Wherein, the interventional fluid pumping device comprises a body, a sheath tube and a sheath tube connecting unit;

[0005] The distal end of the sheath connection unit covers the proximal end of the body, and the sheath connection unit is coaxially arranged with the body;

[0006] A hollow inner cavity is provided inside the sheath tube connection unit, and the distal end of the sheath tube is arranged inside the hollow inner cavity.

[0007] In an optional embodiment, the body includes a shell, and the distal end surface of the sheath connection unit is fixedly connected to the proximal end surface of the shell; or,

[0008] The body comprises a shell and a proximal bearing seat, the proximal bearing seat is arranged at the proximal end of the shell, and the sheath connection unit is fixedly sleeved on the outer peripheral wall of the proximal bearing seat; or,

[0009] The main body includes an outer shell and a proximal bearing seat, the proximal bearing seat is arranged at the proximal end of the outer shell, the distal end face of the sheath connection unit is fixedly connected to the proximal end face of the outer shell, and the sheath connection unit is fixedly sleeved on the outer peripheral wall of the proximal bearing seat.

[0010] In an optional embodiment, the sheath connection unit includes a distal first step hole;

[0011] The housing includes a first proximal step;

[0012] The distal first step hole is sleeved on the proximal first step; or, the distal first step hole is sleeved on the outer peripheral wall of the proximal bearing seat.

[0013] In an optional embodiment, the sheath connection unit is provided with a proximal first step hole and a proximal second step hole, wherein the proximal second step hole is closer to the body than the proximal first step hole;

[0014] The inner diameter of the proximal second step hole is smaller than the inner diameter of the proximal first step hole.

[0015] In an optional embodiment, the distal end of the sheath is nested in the proximal first step hole and the proximal second step hole, and the proximal first step hole is gap-matched with the distal end of the sheath.

[0016] In an optional embodiment, a proximal third step hole is further provided between the distal first step hole and the proximal second step hole, and the proximal third step hole is connected to the distal first step hole via a conical shell.

[0017] In an optional embodiment, a filling unit is provided in the hollow inner cavity to fix the distal end of the sheath tube.

[0018] In an optional embodiment, a filling unit is provided in the gap between the proximal first step hole and the distal end of the sheath tube.

[0019] In an optional embodiment, the roughness of the outer wall surface of the sheath connection unit is smaller than the roughness of the inner wall surface.

[0020] In an optional embodiment, the sheath connection unit and the housing, and / or the sheath connection unit and the proximal bearing seat are connected by welding or thermal fusion.

[0021] In an optional embodiment, the sheath connection unit is provided with at least one notch penetrating through its outer peripheral wall.

[0022] The technical solution of the present invention has the following advantages or beneficial effects:

[0023] (1) The present invention connects the sheath tube and the body of the fluid pumping device by providing an independent sheath tube connection unit, and the sheath tube connection unit covers the proximal end of the body and the distal end of the sheath tube, thereby isolating the components inside the sheath tube connection unit from the blood. The sheath tube connection unit is corrosion-resistant and can avoid the potential safety hazards caused by the corrosion of the components and adhesive materials in the pumping system by blood, and effectively solves the various problems caused by the injection molding or gluing method used in the prior art to connect the sheath tube and the blood pumping device.

[0024] (2) In the present invention, the sheath connection unit is fixedly connected to the housing, or the sheath connection unit is fixedly connected to the proximal bearing seat, or the sheath connection unit is fixedly connected to both the housing and the proximal bearing seat. The connection mating surfaces of the above connection methods can effectively prevent or reduce blood from entering the hollow inner cavity of the sheath connection unit, thereby avoiding or slowing down blood corrosion of the connection between the sheath and the sheath connection unit, ensuring the safety and reliability of the device. Preferably, when the sheath connection unit is connected to the housing and the proximal bearing seat at the same time, its contact surface has a bent shape to form a labyrinth sealing structure, and it is difficult for blood to enter the hollow inner cavity of the sheath connection unit through the sealing structure, that is, the sealing effect of this assembly method is better.

[0025] (3) The inner diameter of the second proximal step hole of the present invention is smaller than the inner diameter of the first proximal step hole. The second proximal step hole can constrain the radial displacement of the sheath tube, thereby making the gap between the outer wall of the sheath tube and the first proximal step hole more uniform. The more uniform the gap is, the easier it is to fill the injection molding material or the bonding material therein, and the distribution of the material is also more uniform, thereby ensuring that the connection strength at each location of the outer wall of the sheath tube is substantially equal, thereby ensuring the stability of the connection.

[0026] (4) The present invention covers the proximal end of the body with the sheath connection unit, and arranges a filling material in the gap between the first step hole at the proximal end and the distal end of the sheath, making full use of the sheath connection unit to block blood from entering the hollow inner cavity of the sheath connection unit, avoiding corrosion of the filling material, and eliminating the problem of reduced sheath connection strength. In addition, the filling material can effectively fix the proximal end of the sheath to the inner wall of the sheath connection unit.

[0027] (5) The roughness of the outer wall surface of the sheath connection unit of the present invention is small, so that blood can smoothly pass through the outer wall surface of the sheath connection unit, reducing the residence time of blood there and reducing the incidence of thrombosis. And the lower surface roughness facilitates the evacuation of the fluid pumping device from the human body. At the same time, the inner wall surface of the sheath connection unit has a larger surface roughness, which can increase the attachment area of ​​the filling material and improve the connection strength between the sheath and the sheath connection unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are used to better understand the present invention and do not constitute an improper limitation of the present invention.

[0029] Figure 1 is a cross-sectional schematic diagram of an interventional fluid pumping device according to an embodiment of the present invention;

[0030] Figure 2 is a three-dimensional schematic diagram of an interventional fluid pumping device according to an embodiment of the present invention;

[0031] Figure 3 is a partial three-dimensional schematic diagram of the proximal end of an invasive fluid pumping device according to an embodiment of the present invention;

[0032] Figure 4 is a cross-sectional schematic diagram of a sheath tube connection unit according to an embodiment of the present invention;

[0033] Figure 5 is a three-dimensional schematic diagram of a sheath tube connection unit according to an embodiment of the present invention;

[0034] Figure 6 It is a schematic diagram of sheath tube connection in the prior art. DETAILED DESCRIPTION

[0035] The following is a description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and conciseness, the description of well-known functions and structures is omitted in the following description.

[0036] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0037] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0038] In the prior art, a blood pumping device works in a patient's body to assist the blood flow of a corresponding organ. For some blood pumping devices, when the device pumps blood from the distal end to the proximal end, the blood will enter the blood pumping device from the distal end to the proximal end accordingly. Therefore, the blood pumping device needs to be injected with perfusion fluid from the proximal end and the distal end, and at least part of the perfusion fluid will be discharged into the blood. However, in some blood pumping devices, the perfusion fluid such as glucose injected into the blood pumping device is completely discharged into the human body after passing through the components in the blood pumping device, causing physical discomfort to the patient. In particular, the perfusion waste fluid containing wear particles entering the human body will cause serious risks such as thrombosis. In addition, during the operation of the blood pumping device, the friction pairs of the bearings and the like will generate a lot of heat, and local high temperature phenomena will occur. In practice, it is necessary to circulate the perfusion fluid to flush the blood pumping motor to take away the wear particles, heat and thrombus. In order to realize the circulation of the perfusion fluid, it is necessary to set a perfusion pipe and a discharge pipe in the blood pumping system. The perfusion tube and the drainage tube are arranged inside the sheath tube to form a sheath tube assembly. When the sheath tube assembly is connected to the proximal end of the blood pumping device, the perfusion tube and the drainage tube are respectively connected to the corresponding pipelines inside the blood pumping device. In the prior art, the sheath tube assembly and the blood pumping device are fixedly connected only by a coating method such as injection molding or gluing. The injection molding and adhesive materials are exposed to the environment over a large area. For example, in an interventional state, the blood directly contacts the injection molding or gluing coating materials over a large area. Figure 6 In the prior art shown, an injection molding or adhesive material 52 is disposed between the sheath and the blood pumping device to connect the two. The injection molding or adhesive material 52 is exposed to the environment over a large area, and especially in an interventional state, the injection molding or adhesive material 52 is in contact with blood over a large area. The weak alkalinity of the blood will gradually corrode the injection molding or adhesive material, causing the connection strength of the sheath assembly to decrease, and even causing the risk of separation of the sheath and the blood pumping device, thereby resulting in low reliability of the device. In addition, during the gradual corrosion of the injection molding or adhesive material 52, the injection molding or adhesive material 52 is slowly released and enters the blood, posing a potential safety hazard to the human body.

[0039] In order to solve at least one of the above problems, the present invention provides an interventional fluid pumping device, wherein the interventional fluid pumping device comprises a body, a sheath tube and a sheath tube connecting unit; the distal end of the sheath tube connecting unit covers the proximal end of the body, and the sheath tube connecting unit is coaxially arranged with the body; a hollow inner cavity is provided inside the sheath tube connecting unit, and the distal end of the sheath tube is arranged inside the hollow inner cavity.

[0040] like Figure 1In the illustrated embodiment, the fluid pumping device shown mainly includes three parts: a body, a sheath 113, and a sheath connection unit 116. The body includes a housing 108, and multiple components such as a magnetic steel 103 and a winding 104 arranged inside the housing 108. In the above embodiment, the housing 108 is an independent part, and can be processed separately and then assembled with components such as the magnetic steel 103 and the winding 104. In other embodiments, in order to reduce the diameter of the fluid pumping device and improve its interventional performance, the stator core is used as the housing of the fluid pumping device; and in the interventional state, the outer wall surface of the stator core is directly in contact with blood or tissue. A rotating shaft 105 is penetrated inside the magnetic steel 103. An impeller 101 is arranged at the far end of the rotating shaft 105, and the impeller is arranged inside the blood channel 102. The rotating shaft 105 is driven by electric current to drive the impeller 101 to rotate, thereby sucking blood from the distal end into the interior of the blood channel 102, and then pumping the blood out from the outlet 201 provided on the outer wall of the blood channel 102. The distal end of the housing 108 is also provided with a distal bearing seat 109 and a distal bearing 106, and the distal bearing 106 is assembled in the distal bearing seat 109, and the distal bearing 106 is used to penetrate and support the rotating shaft 105. The distal bearing seat 109 is fixed to the distal end of the housing 108. A distal cover 107 is also provided between the blood channel 102 and the distal bearing seat 109, and the distal cover 107 is sleeved on the distal end of the housing 108. The proximal end of the housing 108 is also provided with a proximal bearing seat 111 and a proximal bearing 110. The proximal bearing 110 is assembled on the proximal bearing seat 111 and is used to pass through and support the rotating shaft 105. The proximal bearing seat 111 is assembled on the proximal end of the housing 108. The body is also provided with a proximal cover 112 for closing the proximal end of the body. In some embodiments, the proximal cover 112 is embedded in the proximal bearing seat 111.

[0041] like Figure 1In the embodiment shown, the distal end of the sheath connection unit 116 covers the proximal end of the body, and the sheath connection unit 116 is coaxially arranged with the body; a hollow inner cavity is provided inside the sheath connection unit 116, and the distal end of the sheath 113 is fixed inside the hollow inner cavity. The sheath connection unit 116 is an independent entity component, and after the main body is partially assembled, the sheath connection unit 116 can be sleeved on the proximal end of the body to achieve the coating of the proximal end of the body. The sheath connection unit 116 can be made of biocompatible metal material or non-metallic material. Preferably, it is made of SUS316L series material. When made of metal materials such as SUS316L, a sheath connection unit with a preset structural shape and size can be obtained by mechanical processing; when made of non-metallic materials, a sheath connection unit with a preset structural shape and size can be obtained by injection molding, or additive manufacturing. In some embodiments, an irrigation tube 114 and a drainage tube 115 are also provided inside the sheath. The sheath tube 113, the perfusion tube 114 and the drainage tube 115 constitute a sheath tube assembly. When the sheath tube assembly is connected to the body, the perfusion tube 114 and the drainage tube 115 are respectively connected to the corresponding perfusion liquid flow channels in the body, so that the perfusion liquid enters the body from the perfusion tube 114, and the perfusion waste liquid is discharged from the body to the drainage tube 115. Regardless of whether the sheath tube connection unit is made of metal material or non-metal material, it is necessary to further set a hollow inner cavity inside the sheath tube connection unit to fix the distal end of the connecting sheath tube 113. It can be seen from the above description that the present invention connects the sheath tube and the body of the fluid pumping device by setting an independent sheath tube connection unit, and the sheath tube connection unit covers the proximal end of the body and the distal end of the sheath tube, so as to isolate the components inside the sheath tube connection unit from the blood. The sheath connection unit is corrosion-resistant and can avoid potential safety hazards caused by blood corroding components and adhesive materials in the pumping system, and effectively solves various problems caused by connecting the sheath and the blood pumping device by injection molding or gluing methods used in the prior art.

[0042] In an optional embodiment, the body includes a shell 108, and the distal end face of the sheath connection unit 116 is fixedly connected to the proximal end face of the shell; or, the body includes a shell 108 and a proximal bearing seat 111, the proximal bearing seat 111 is disposed at the proximal end of the shell 108, and the sheath connection unit 116 is fixedly sleeved on the outer peripheral wall of the proximal bearing seat 111; or, the body includes a shell 108 and a proximal bearing seat 111, the proximal bearing seat 111 is disposed at the proximal end of the shell 108, the distal end face of the sheath connection unit 116 is fixedly connected to the proximal end face of the shell 108, and the sheath connection unit 116 is fixedly sleeved on the outer peripheral wall of the proximal bearing seat 111. Figure 3 and4 In the illustrated embodiment, the proximal end of the housing 108 includes an end face 301, and the distal end of the sheath connection unit includes a distal end face 407; when the sheath connection unit covers the proximal end of the body, the end face 301 and the distal end face 407 are assembled together, and the sheath connection unit 116 can be connected to the housing 108 by means such as welding or thermal fusion. Preferably, a step structure can be provided at the proximal end of the housing 108 to facilitate the sleeve and fixation of the sheath connection unit. In some embodiments, the body includes a housing 108 and a proximal bearing seat 111, and the inner hole of the proximal end of the housing 108 is adapted to the outer diameter of the proximal bearing seat 111, and then the proximal bearing seat 111 is embedded in the inner hole of the proximal end of the housing 108. Exemplarily, the proximal bearing seat 111 and the housing 108 can be connected by welding, threaded connection or thermal fusion connection, etc. Of course, the proximal bearing seat 111 can also be connected to the proximal end of the housing 108 by other assembly methods. The sheath connection unit 116 is fixedly sleeved on the outer peripheral wall 302 of the proximal bearing seat 111. Figure 1 and 3 As shown, a part of the proximal bearing seat 111 is arranged in the inner hole of the proximal end of the housing 108, and the other part is exposed from the inner hole of the housing 108, thereby forming a step structure with the housing 108. Correspondingly, a distal first step hole 402 is formed at the left end of the sheath connection unit, and the inner wall of the distal first step hole 402 is assembled with the outer peripheral wall 302 of the proximal bearing seat 111 to assemble the sheath connection unit on the proximal end of the body. The sheath connection unit and the proximal bearing seat 111 can be fixed by welding, thermal fusion or threaded connection. In some other embodiments, the main body includes a shell 108 and a proximal bearing seat 111, the proximal bearing seat 111 is disposed at the proximal end of the shell 108, and partially exposes the inner hole of the shell 108 to form a step structure with the shell 108, the distal end face of the sheath connection unit 116 is fixedly connected to the proximal end face 301 of the shell 108, and the sheath connection unit 116 is fixedly sleeved on the outer peripheral wall 302 of the proximal bearing seat 111. Compared with the first two embodiments, in this embodiment, the sheath connection unit is connected to the shell 108 and the proximal bearing seat 111 at the same time, and the connection surface can be fixed by welding, thermal fusion or threaded connection. This connection method has a larger contact area, thereby effectively improving the assembly strength of the sheath connection unit. More advantageously, when the sheath connection unit is connected to the shell and the proximal bearing seat at the same time, its contact surface has a bent shape (see Figure 1The joint between the proximal end of the body and the sheath connection unit shown in the middle cross-sectional view) forms a labyrinth seal structure, making it difficult for blood to enter the hollow inner cavity of the sheath connection unit through the bent joint of the mating surface. In addition, no matter the sheath connection unit is fixedly connected to the outer shell, or the sheath connection unit is fixedly connected to the proximal bearing seat, or the sheath connection unit is fixedly connected to the outer shell and the proximal bearing seat at the same time, the connection mating surface can effectively prevent or reduce blood from entering the hollow inner cavity of the sheath connection unit, thereby avoiding or slowing down blood corrosion of the connection between the sheath and the sheath connection unit, and ensuring the safety and reliability of the device.

[0043] In an optional embodiment, the sheath connection unit includes a distal first step hole 402; the housing includes a proximal first step (not shown in the figure); the distal first step hole 402 is sleeved on the proximal first step; or, the distal first step hole is sleeved on the outer peripheral wall 302 of the proximal bearing seat. In some embodiments, the housing 108 is often made of corrosion-resistant materials. At this time, it can be given priority to fix the sheath connection unit on the housing 108, so as to effectively utilize the corrosion resistance of the housing to prevent blood from corroding the pumping device body and preventing it from entering the interior of the sheath connection unit. To this end, a step structure can be machined on the housing 108, and the interior of the distal first step hole 402 of the sheath connection unit is matched and fixed with the outer peripheral wall of the step structure. At the same time, the distal end face 407 of the sheath connection unit is matched and fixed with the radially extending end face of the step structure of the housing. The same sealing principle as described above, two mating connection surfaces can be formed by assembling the step structure on the shell, and the two mating connection surfaces form a bent labyrinth sealing structure, thereby effectively preventing blood from entering the mating surface, preventing blood from corroding the assembly structure inside the sheath connection unit, and ensuring the stability of the connection. In some embodiments, the proximal inner hole of the sheath connection unit is also provided with a chamfer or fillet 401, so as to facilitate the sheath connection unit to be sleeved on the body.

[0044] In an optional embodiment, the sheath connection unit is provided with a proximal first step hole 405 and a proximal second step hole 404, wherein the proximal second step hole is closer to the body than the proximal first step hole; and the inner diameter of the proximal second step hole 404 is smaller than the inner diameter of the proximal first step hole 405. Figure 1In the illustrated embodiment, in the assembled state, the sheath is sleeved in the proximal first step hole and the proximal second step hole. In an optional embodiment, when the distal end of the sheath is nested in the proximal first step hole and the proximal second step hole, the proximal first step hole is matched with the distal end clearance of the sheath. Preferably, the aperture of the proximal first step hole is 0.05-0.3mm larger than the outer diameter of the sheath. Compared with the method in which the second step hole is not provided in the sheath connection unit, in this embodiment, since the inner diameter of the proximal second step hole is smaller, it can constrain the radial displacement of the sheath, so that the gap between the outer wall of the sheath and the proximal first step hole is more uniform, that is, the size of the outer wall of the sheath from the proximal first step hole is basically equal. In some embodiments, the more uniform the gap is, the easier it is to fill the injection molding material or the bonding material therein, and the distribution of the material is also more uniform, thereby ensuring that the connection strength of each part of the outer wall of the sheath is basically equal, and ensuring the stability of the connection.

[0045] In an optional embodiment, a proximal third step hole 406 is further provided between the distal first step hole 402 and the proximal second step hole 404, and the proximal third step hole is connected to the distal first step hole via a conical housing 403. Preferably, the aperture of the proximal third step hole 406 is 0.05-0.3 mm larger than the outer diameter of the sheath tube. Figure 1 and 4 In the embodiment shown, the proximal end size of the sheath connection unit needs to match the outer diameter of the sheath, and the distal end needs to match the proximal end size of the body, so that the overall orientation of the sheath connection unit is as follows: Figure 4 In order to make the pumping system as a whole have a complete streamlined shape to facilitate the insertion and withdrawal of instruments from the human body, in one embodiment of the present invention, a conical housing 403 is provided between the proximal third step hole and the distal first step hole to achieve a size transition. Thus, the pumping device presents a streamlined shape at the distal end of the sheath.

[0046] In an optional embodiment, a filling unit is provided in the hollow inner cavity to fix the distal end of the sheath tube. In an optional embodiment, a filling unit is provided in the gap between the proximal first step hole and the distal end of the sheath tube. Figure 1 In the embodiment shown, a filling unit 117 may be provided at various locations of the hollow inner cavity of the sheath connection unit. For example, the filling unit may be an adhesive material, etc. For example, an adhesive may be provided. Figure 1As shown, the adhesive is filled in the cavity surrounded by the sheath connection unit and the proximal cover 112, so as to fix the sheath, the perfusion tube and the drainage tube and other components to the proximal end of the body. In particular, when the adhesive is filled in the gap between the proximal first step hole and the distal end of the sheath, it can effectively fix the proximal end of the sheath to the inner wall of the sheath connection unit. It can be seen from the foregoing description that after the proximal end of the body is covered by the sheath connection unit, the blood will be isolated from the outside of the hollow inner cavity of the sheath connection unit, that is, the blood cannot enter the hollow interior; at this time, there is no need to worry about the blood entering the hollow inner cavity and corroding the adhesive material, thereby achieving a stable connection of the distal end of the sheath, so that the fluid pumping device has good safety and reliability.

[0047] In an optional embodiment, the roughness of the outer wall surface of the sheath connection unit is less than the roughness of the inner wall surface. In some embodiments, the roughness of the outer wall surface is as small as possible, and the surface roughness of the outer wall surface is preferably Ra0.8 or below, so that the blood can smoothly pass through the outer wall surface of the sheath connection unit, reducing the residence time of the blood there, so as to reduce the incidence of thrombosis. In addition, the lower surface roughness also facilitates the evacuation of the fluid pumping device from the human body. In some embodiments, an anticoagulant and / or lubricating and / or antibacterial coating may be provided on the outer wall surface. In some embodiments, the surface roughness of the inner wall surface is as large as possible, and the preferred surface roughness is Ra3.2 or above, and it can be roughened if necessary. A larger surface roughness can increase the attachment area of ​​the filling material and improve the connection strength between the sheath and the sheath connection unit.

[0048] In an optional embodiment, the sheath connection unit and the housing, and / or the sheath connection unit and the proximal bearing seat are connected by welding or thermal fusion. In some embodiments, when the sheath connection unit is made of non-metallic material, it can be connected to the corresponding component by thermal melting. When it is made of metal material, it can be connected by welding.

[0049] In an optional embodiment, the sheath connection unit is provided with at least one notch 501 penetrating through its outer peripheral wall. Figure 4 In the embodiment shown, at least one notch is provided at the left bell mouth of the sheath connection unit to avoid the routing of the perfusion tube or other pipelines.

[0050] The above specific implementation methods do not constitute a limitation on the scope of protection of the present invention. After considering the specification and practicing the technical solutions disclosed in this application, those skilled in the art will easily think of other implementation methods of the present disclosure. This application is intended to cover any modification, use or adaptive changes of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary technical means in the technical field that are not disclosed in the present disclosure. The description and examples are regarded as exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

[0051] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. An interventional fluid pumping device, Features: It includes a body, a sheath tube and a sheath tube connecting unit; The distal end of the sheath connection unit covers the proximal end of the body, and the sheath connection unit is coaxially arranged with the body; A hollow inner cavity is provided inside the sheath tube connection unit, and the distal end of the sheath tube is arranged inside the hollow inner cavity.

2. The interventional fluid pumping device according to claim 1, characterized in that: The body comprises a shell, and the distal end surface of the sheath connection unit is fixedly connected to the proximal end surface of the shell; or, The body comprises a shell and a proximal bearing seat, the proximal bearing seat is arranged at the proximal end of the shell, and the sheath connection unit is fixedly sleeved on the outer peripheral wall of the proximal bearing seat; or, The main body includes an outer shell and a proximal bearing seat, the proximal bearing seat is arranged at the proximal end of the outer shell, the distal end face of the sheath connection unit is fixedly connected to the proximal end face of the outer shell, and the sheath connection unit is fixedly sleeved on the outer peripheral wall of the proximal bearing seat.

3. The interventional fluid pumping device according to claim 2, characterized in that: The sheath connection unit comprises a distal first step hole; The housing includes a first proximal step; The distal first step hole is sleeved on the proximal first step; or, the distal first step hole is sleeved on the outer peripheral wall of the proximal bearing seat.

4. The interventional fluid pumping device according to claim 3, characterized in that: The sheath connection unit is provided with a first proximal step hole and a second proximal step hole, wherein the second proximal step hole is closer to the body than the first proximal step hole; The inner diameter of the proximal second step hole is smaller than the inner diameter of the proximal first step hole.

5. The interventional fluid pumping device according to claim 4, characterized in that: The distal end of the sheath tube is nested in the proximal first step hole and the proximal second step hole, and the proximal first step hole is gap-matched with the distal end of the sheath tube.

6. The intrusive fluid pumping device according to claim 5, characterized in that: A proximal third step hole is also provided between the distal first step hole and the proximal second step hole, and the proximal third step hole is connected to the distal first step hole through a conical shell.

7. The interventional fluid pumping device according to any one of claims 1 to 6, characterized in that: A filling unit is arranged in the hollow inner cavity to fix the distal end of the sheath tube.

8. The intrusive fluid pumping device according to claim 7, characterized in that: A filling unit is provided in the gap between the proximal first step hole and the distal end of the sheath tube.

9. The interventional fluid pumping device according to any one of claims 1 to 6, characterized in that: The roughness of the outer wall surface of the sheath tube connection unit is smaller than the roughness of the inner wall surface.

10. The interventional fluid pumping device according to any one of claims 1 to 6, characterized in that: The sheath tube connection unit and the housing, and / or the sheath tube connection unit and the proximal bearing seat are connected by welding or thermal fusion.

11. The interventional fluid pumping device according to any one of claims 1 to 6, characterized in that: The sheath tube connection unit is provided with at least one notch penetrating through its outer peripheral wall.

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