Catheter pump

Abstract

According to the guide pipe pump, the flexible shaft and the hard shaft in the guide pipe pump are mechanically connected and fixed through the connecting assembly, the connecting mode is not limited by materials of the flexible shaft and the hard shaft, and in other words, connection between the metal flexible shaft and the metal hard shaft can be achieved through mechanical connection; moreover, the mechanical connection can also realize the connection between the metal material flexible shaft and the non-metal material hard shaft, that is, the flexible shaft and the hard shaft are connected through the connecting assembly, so that the selection range of the hard shaft material is larger, and the manufacturing of the driving shaft is more flexible; particularly, the hard shaft made of the non-metal material has good biocompatibility on the basis of meeting the requirement for the connecting roughness of the hard shaft and the impeller, then the potential risk of the hard shaft working on an organism can be reduced to the maximum extent, and the reliability of connecting the flexible shaft and the hard shaft through the connecting assembly is high.

Description

Technical Field

[0001] This application relates to the field of medical device technology, specifically to a catheter pump. Background Technology

[0002] The catheter pump includes a drive unit, a drive shaft, and an impeller. The drive shaft includes a flexible shaft and a rigid shaft connected together. The proximal end of the flexible shaft is connected to the drive unit, and the distal end is connected to the rigid shaft. The impeller is mounted on the rigid shaft. The drive unit drives the rigid shaft to rotate through the flexible shaft, which in turn drives the impeller to rotate. The rotation of the impeller realizes the blood pumping function.

[0003] The reliability and safety of connections between flexible and rigid shafts are among the most important issues that those skilled in the art have always been concerned about. Summary of the Invention

[0004] The purpose of this application is to provide a duct pump in which the drive shaft, including its flexible shaft and rigid shaft, is connected by a connecting assembly. This connection method is not limited by the materials of the flexible shaft and rigid shaft, and offers greater molding flexibility.

[0005] This application provides a conduit pump, including the following components: Drive unit; A drive shaft includes a flexible shaft, a rigid shaft, and a connecting assembly. The proximal end of the flexible shaft is coupled to the drive device, and the distal end of the flexible shaft is connected to the proximal end of the rigid shaft via the connecting assembly. The drive device drives the rigid shaft to rotate via the flexible shaft. The pump head assembly includes an impeller, a pump housing, and a proximal bearing. The impeller is fitted onto the rigid shaft, and the rigid shaft is rotatably supported inside the pump housing via the proximal bearing.

[0006] Compared to the current technology where flexible and rigid shafts are connected by welding, the flexible and rigid shafts in this application are mechanically connected and fixed by a connecting assembly. This connection method is not limited by the materials of the flexible and rigid shafts. That is, the mechanical connection can not only realize the connection between metal flexible shafts and metal rigid shafts, but also the connection between metal flexible shafts and non-metallic rigid shafts. In other words, the connection of the flexible and rigid shafts in this application through the connecting assembly allows for a wider range of rigid shaft material choices and more flexible manufacturing of the drive shaft. In particular, the non-metallic rigid shaft, while meeting the roughness requirements for connection with the impeller, has good biocompatibility, which can minimize the potential risks to organisms from the operation of the rigid shaft. Furthermore, the connection between the flexible and rigid shafts through the connecting assembly has high reliability.

[0007] In one example, the connection point between the flexible shaft and the rigid shaft is located on the proximal side of the proximal bearing.

[0008] In one example, the connecting component is at least partially located on the proximal side of the proximal bearing.

[0009] In one example, the connecting assembly is located entirely outside the proximal bearing; Alternatively, the connecting assembly may be located outside the proximal bearing, with the remainder located inside the proximal bearing.

[0010] In one example, the connecting assembly includes a sleeve with a central through-hole, the proximal end of the rigid shaft having a first shaft segment with a non-circular outer contour, the central through-hole having a first inner bore segment, the first shaft segment being at least partially inserted into the first inner bore segment, the first inner bore segment cooperating with the first shaft segment to restrict circumferential rotation of the sleeve and the rigid shaft.

[0011] In one example, the outer peripheral wall of the first shaft segment includes at least one first plane extending parallel to the central axis of the rigid shaft, and the inner peripheral wall of the first inner hole segment includes a second plane, the first plane cooperating with the second plane to restrict the circumferential rotation of the sleeve and the rigid shaft.

[0012] In one example, the drive shaft further includes a bushing located at the distal end of the sleeve, the distal end of the bushing being capable of abutting against a proximal bearing inside the pump head assembly of the duct pump to limit the extreme position of the rigid shaft's distal movement in the duct pump.

[0013] In one example, a limiting portion is provided on the shaft segment outside the sleeve of the rigid shaft, and the bushing is located between the sleeve and the limiting portion.

[0014] In one example, one of the opposing end faces of the sleeve and the bushing is provided with a protrusion that protrudes axially, and the other is provided with a recess that mates with the protrusion.

[0015] In one example, the rigid shaft further includes a second shaft segment, which is a cylindrical segment located distal to the first shaft segment. The outer peripheral wall of the first shaft segment includes at least one first plane, which is recessed relative to the outer peripheral wall of the second shaft segment toward the central axis of the rigid shaft. The inner peripheral wall of the first inner hole segment includes a second plane, and the first plane and the second plane cooperate to restrict the circumferential rotation of the sleeve and the rigid shaft. The distal end of the first plane extends out of the first inner hole segment and is connected to the outer peripheral wall of the second shaft segment through the stepped surface. The limiting part is the stepped surface, and the bushing is limited between the sleeve and the stepped surface.

[0016] In one example, the connecting assembly further includes at least one pin, the sleeve is provided with a first through hole penetrating the peripheral wall of the first inner hole section, the first shaft section is provided with a socket coaxially disposed with the first through hole, and the pin is fixedly connected to the inside of the first through hole and the socket.

[0017] In one example, the outer peripheral wall of the first shaft segment includes two parallel first planes and an arcuate wall connecting the two first planes. The insertion port is a notch provided on the arcuate wall, and the notch is isolated from the hollow inner cavity of the rigid shaft.

[0018] In one example, the central through hole further includes a second inner hole section, the distal end of the flexible shaft is located in the second inner hole section, and a binder is filled between the outer peripheral wall of the flexible shaft and the inner peripheral wall of the second inner hole section.

[0019] In one example, at least one process through hole is provided on the peripheral wall of the second inner hole section for introducing the binder between the outer peripheral wall of the flexible shaft and the inner peripheral wall of the second inner hole section.

[0020] In one example, the flexible shaft is located inside the second inner hole section as a braided shaft section, and the braided filaments of the braided shaft section are also filled with the binder.

[0021] In one example, the flexible shaft located inside the second inner hole section is a braided shaft section, and the braided filaments of the braided shaft section are also filled with the binder. During molding, the binder is first filled between the braided filaments to form a whole, and then the braided shaft section is inserted into the second inner hole section, and the binder is filled between the braided shaft section and the inner peripheral wall of the second inner hole section. Alternatively, the flexible shaft located inside the second inner hole section is a braided shaft section, and the braided filaments of the braided shaft section are also filled with the binder. At least one process through hole is provided on the peripheral wall of the second inner hole section. During molding, the binder enters the second inner hole section through the process through hole to fill between the braided filaments and between the braided shaft section and the inner peripheral wall of the inner hole section.

[0022] In one example, the rigid shaft is a non-metallic rigid shaft, the flexible shaft is a metallic flexible shaft, the flexible shaft is fixedly connected to the connecting assembly by welding, and the rigid shaft is connected to the connecting assembly by non-welding.

[0023] In one example, the hard shaft is a ceramic material hard shaft.

[0024] In one example, the bushing is a ceramic material bushing. Attached Figure Description

[0025] Figure 1This is a schematic diagram of the duct pump in a specific embodiment of this application; Figure 2 This is a schematic diagram of a catheter pump implanted in the heart in one specific embodiment of this application; Figure 3 This is a partial structural diagram of the duct pump in a specific embodiment of this application; Figure 4 for Figure 3 Enlarged schematic diagram of point A of the structure shown; Figure 5 This is a schematic diagram of the drive shaft structure in one embodiment of this application; Figure 6 for Figure 5 An exploded view of the drive shaft shown. Figure 7 for Figure 5 The diagram shows the structure of the sleeve in the drive shaft. Figure 8 for Figure 7 A structural schematic diagram of the sleeve from another perspective; Figure 9 for Figure 5 A schematic diagram of the rigid shaft in the drive shaft is shown. Figure 10 This is a graph showing the wear amount versus time relationship between a metal hard shaft and a ceramic hard shaft in one embodiment of this application.

[0026] The annotations in the attached figures are explained below: 1000 duct pump; 100 drive unit; 200 coupler; 310 duct; 320 pump head assembly; 321 impeller; 3211 hub; 3212 blade; 322 pump casing; 323 proximal bearing; 330 flexible support; 400 Drive shaft; 1 Flexible shaft; 11 Braided shaft section; 2 Hard shaft; 21 First shaft section; 211 First plane; 212 Limiting part; 213 Insertion port; 214 Arc-shaped wall; 22 Second shaft section; 3 Connecting assembly; 31 Sleeve; 31A Central through hole; 31A1 First inner hole section; 31A2 Second inner hole section; 311 Protrusion; 312 Process through hole; 313 First through hole; 314 Second plane; 32 Pin; 4 Shaft sleeve; 41 Recess. Detailed Implementation

[0027] The inventors of this application conducted extensive research on the structure of the drive shaft in ducted pumps and found that the flexible and rigid shafts in current ducted pumps are basically made of metal and are fixed together by welding. Due to connection requirements, the rigid shaft in current technology can only be made of metal. Because the rigid shaft needs to meet requirements such as bearing the impeller and biocompatibility, the availability of suitable metal materials for rigid shaft processing is limited, thus restricting its machining. Furthermore, rigid shafts made of metal also face technical problems such as rusting and high processing difficulty during use.

[0028] Although current technology involves coating the surface of rigid shafts to prevent them from rusting, the stability of the coating process on thinner shafts is a challenge. There may be issues with the coating's adhesion, and the detached coating could pose a potential risk to living organisms.

[0029] The main purpose of this application is to find a solution to at least one of the above-mentioned technical problems.

[0030] To enable those skilled in the art to better understand the technical solutions of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Please refer to Figures 1 to 2 , Figure 1 This is a schematic diagram of the duct pump in a specific embodiment of this application; Figure 2 This is a schematic diagram of a catheter pump implanted in the heart in one specific embodiment of this application.

[0032] This application provides a catheter pump 1000, which can be applied in scenarios requiring guidewire intervention. Please refer to... Figure 1 The duct pump 1000 includes a drive unit 100 and a pump head assembly 320. The drive unit 100 includes a housing and a motor located within the housing.

[0033] The catheter pump 1000 further includes a coupler 200, a catheter 310, and a flexible support 330. In use, the drive unit 100 is typically located outside the subject (who may be human), while the pump head assembly 320 can be inserted into the subject's body, specifically in the left ventricle, for example... Figure 2 As shown, this device assists the heart in pumping blood, reducing the burden on the heart. The pump head assembly 320 can assist the left ventricle by pumping blood from the left ventricle into the aorta. Of course, the pump head assembly 320 can also be inserted into other target locations of the subject via interventional surgery, for example, the pump head assembly 320 can be inserted into the right ventricle, with the catheter pump 1000 used to assist the right ventricle. Furthermore, the pump head assembly 320 can also be inserted into blood vessels or other organs.

[0034] The flexible support 330 is connected to the distal end of the pump head assembly 320. During the insertion of the pump head assembly 320 into the subject's body, the flexible support 330 can guide the insertion of components such as the pump housing 322. After the pump head assembly 320 and other components are inserted into the desired position in the body, during the operation of the catheter pump 1000, the flexible support 330 can maintain the posture of the pump head assembly 320 in the heart, thereby avoiding damage to the patient's tissues. In some embodiments, the distal end of the flexible support 330 is a flexible end that can support the ventricular wall in a non-invasive or non-damaging manner, separating the blood inlet of the pump head assembly 320 from the ventricular wall. The distal end of the flexible support 330 can be arc-shaped, or it can be a coiled flexible protrusion, such as... Figure 1 As shown. Those skilled in the art should understand that the illustrated shape is merely exemplary, and the flexible support 330 can be in any other suitable shape, as long as it achieves the above-described purpose.

[0035] In one example, the conduit 310 has a hollow structure, and a drive shaft 400 passes through the interior of the conduit 310 (see [link to documentation]). Figure 3 and Figure 4 (Cross-section lines are not shown in the figures). In this embodiment, the drive device 100 includes a housing and a motor located within the housing, the housing having an internal cavity to accommodate the motor. The transmission method between the motor and the drive shaft 400 can be magnetic coupling or eddy current coupling. The motor is connected to the conduit 310 and the proximal end of the drive shaft 400 via a coupler 200 and is configured as a power component to provide power. The coupler 200 can be detachably mounted on the drive device 100. Typically, the coupler 200 is also provided with a filling port, through which external filling fluid can be injected into the conduit to flush or lubricate components such as bearings in the pump head assembly 320.

[0036] When the coupler 200 is engaged with the drive unit 100, the power output end of the motor is coupled to the proximal end of the drive shaft 400 to drive the drive shaft 400 to rotate, and the distal end of the conduit 310 is connected to the pump head assembly 320. The pump head assembly 320 includes a pump housing 322, a proximal bearing 323, and an impeller 321, with the impeller 321 located inside the pump housing 322.

[0037] The pump housing 322 includes an internal support (not shown in the figure). This support can be a metal lattice made of alloys such as nickel or titanium, with a mesh design to facilitate radial expansion and contraction. The pump housing 322 also includes a membrane mounted on the support. The membrane covers the middle of the support to form a fluid channel, and the area not covered by the membrane at the distal end of the support forms a blood inlet. The area not covered by the membrane at the proximal end of the support forms a blood outlet section. The support also has distal legs extending distally from the blood inlet and proximal legs extending proximally from the blood outlet. The distal legs are fixedly connected to the flexible support 330 and the distal bearing chamber, while the proximal legs are fixedly connected to the proximal bearing chamber and other components.

[0038] The aforementioned pump head assembly 320 can be a foldable blood pump. During the delivery phase, the pump head assembly 320 is radially compressed within the sheath of the interventional sheath, delivering blood at a smaller diameter to improve the permeability of the pump head assembly 320 within the body and reduce damage to the human body. After the pump head assembly 320 is delivered to the designated location, such as after exiting the sheath, the pump head assembly 320 radially expands, restoring to a larger working diameter to obtain better hydraulic performance, such as supporting a larger flow rate.

[0039] Specifically, the impeller 321 is supported inside the bracket. The impeller 321 includes a hub 3211 and blades 3212. The hub 3211 is fixed to the impeller shaft, and typically the hub 3211 has a central hole in its center, into which the impeller shaft is inserted. The two ends of the impeller shaft are supported within the pump housing 322 by a near-end bearing 323 and a far-end bearing (not shown in the figure). In this embodiment, the blades 3212 are connected to the hub 3211. Specifically, the blades 3212 are connected to the outer wall of the hub 3211. The blades 3212 can be integrally formed with the hub 3211, resulting in high forming efficiency and eliminating the need for assembly, thus improving the production efficiency of the impeller 321. Alternatively, the blades 3212 and hub 3211 can be separate structures, with the blades 3212 and hub 3211 being processed separately, and the blades 3212 forming an integral structure with the hub 3211 through an assembly process. Thus, the manufacturing processes for blade 3212 and hub 3211 are relatively simple. The number of blades 3212 is at least one; that is, the number of blades 3212 can be one, or more than one, such as two, three, or other numbers. Each blade 3212 extends spirally along a direction parallel to the central axis of hub 3211. When there are two or more blades 3212, all blades 3212 are approximately parallel to each other and extend spirally along the central axis of hub 3211. In one example, one end of all blades 3212 can start from the same section of hub 3211 and extend spirally along the central axis to another section of hub 3211.

[0040] For the foldable pump head assembly 320, the impeller 321 is a foldable impeller with a radial compression configuration and a radial expansion configuration. The blades 3212 have an outer edge of the blades away from the hub 3211. In the radial compression configuration, the outer edge of the blades of the impeller 321 is close to the hub 3211; in the radial expansion configuration, the outer edge of the blades 3212 is away from the hub 3211. The impeller 321 is in a static or pumping operation state in the radial expansion configuration.

[0041] In this embodiment, the drive shaft 400 includes a flexible shaft 1 and a rigid shaft 2. The proximal end of the flexible shaft 1 is coupled to the drive device 100, and the rigid shaft 2 is connected to the distal end of the flexible shaft 1. The distal end of the rigid shaft 2 is connected to the hub 3211. Specifically, the rigid shaft 2 can be an impeller shaft as described above. The impeller 321 is sleeved on the rigid shaft 2, and the rigid shaft 2 is rotatably supported inside the pump housing 322 by a proximal bearing 323. The drive device 100 drives the rigid shaft 2 to rotate via the flexible shaft 1, which in turn drives the impeller 321 to rotate. The impeller 321 is driven to rotate, drawing blood from the blood inlet of the pump housing 322 into the pump housing 322, and then pumping it out from the blood outlet of the pump housing 322, thereby realizing the pump head assembly 320 pumping and suctioning liquid. Both the flexible shaft 1 and the rigid shaft 2 can be hollow structures. Figure 6 and Figure 9 The hollow hole 2A of the hard shaft 2 is shown in the figure.

[0042] In this embodiment, the drive shaft 400 further includes a connecting component 3. The distal end of the flexible shaft 1 is connected to the proximal end of the rigid shaft 2 via the connecting component 3. That is, the connecting component 3 can connect the flexible shaft 1 and the rigid shaft 2 into an integral structure. When the motor of the drive device 100 rotates, the flexible shaft 1 drives the rigid shaft 2 to rotate synchronously. The flexible shaft 1 can be at least partially a braided shaft, which is formed by braiding one or more strands of braided yarn. The flexible shaft 1 has good flexibility and can bend and deform with the guide tube 310. The braided yarn can be a flexible metal wire.

[0043] The rigid shaft 2 can be made of either a metallic or non-metallic material. In one example, the rigid shaft 2 can be a metal shaft with a coating on its surface, such as a diamond-like carbon (DLC) coating, which offers excellent wear resistance, long service life, and corrosion resistance. In another example, the rigid shaft 2 can be a non-metallic material, such as a ceramic shaft. Ceramic shafts can have a surface roughness of Ra0.1, which is relatively low. Compared to metallic shafts, ceramic materials offer higher hardness and wear resistance. Please refer to [link to relevant documentation]. Figure 10 Furthermore, ceramic hard shafts avoid the problem of metal hard surface coating peeling off, have good biocompatibility, and their processing technology is relatively simple.

[0044] Compared to the current technology where the flexible shaft 1 and the rigid shaft 2 are connected by welding, the flexible shaft 1 and the rigid shaft 2 in this application are mechanically connected and fixed by the connecting component 3. This is not limited by the materials of the flexible shaft 1 and the rigid shaft 2. That is, the mechanical connection can not only realize the connection between metal flexible shafts and metal rigid shafts, but also the connection between metal flexible shafts and non-metallic rigid shafts. In other words, the flexible shaft and the rigid shaft are connected by the connecting component in this application. This allows for a wider range of choices for the rigid shaft material and more flexible manufacturing of the drive shaft. In particular, the non-metallic rigid shaft 2, while meeting the roughness requirements for connection with the impeller, has good biocompatibility, which can minimize the potential risks to organisms from the operation of the rigid shaft 2. Furthermore, the connection between the flexible shaft 1 and the rigid shaft 2 by the connecting component 3 has high reliability.

[0045] In one specific embodiment, the rigid shaft 2 can be a non-metallic rigid shaft, and the flexible shaft 1 is a metallic flexible shaft. The flexible shaft 1 is fixedly connected to the connecting component 3 by welding, resulting in a relatively strong connection. Because the rigid shaft 2 is a non-metallic material, the rigid shaft 2 and the connecting component 3 can be connected by non-welding methods, such as insertion, riveting, or bonding. The specific methods of non-welding connection between the rigid shaft 2 and the connecting component 3 will be described in detail later. In this embodiment, the flexible shaft 1 is made of metallic material, which has good flexibility and can better meet the deformation requirements of installation. The rigid shaft 2 is made of non-metallic material, which can minimize the potential risks to organisms and is conducive to the safe and reliable operation of the tubular pump 1000.

[0046] Please refer to Figure 3 In this embodiment, the connection position of the flexible shaft 1 and the rigid shaft 2 is located on the proximal side of the proximal bearing 323, which facilitates the installation and positioning of the connecting assembly 3.

[0047] In one specific embodiment, the connecting component 3 can be at least partially located on the proximal side of the proximal bearing 323. That is, the connecting component 3 can be completely located outside the proximal bearing 323. The connecting component 3 does not occupy the internal space of the proximal bearing 323, and there is no need to change the current structure of the proximal bearing 323, saving the modification cost of the current conduit pump 1000. Of course, the connecting component 3 can also be partially located outside the proximal bearing 323, with the remaining part located inside the proximal bearing 323. In this case, the connecting component 3 can be made of wear-resistant ceramic material, covering the outside of the rigid shaft 2 and rubbing against the proximal bearing 323. Both the flexible shaft 1 and the rigid shaft 2 can be made of metal materials and directly welded together. The addition of the connecting component makes the connection between the flexible shaft 1 and the rigid shaft 2 more secure and less prone to breakage, and avoids the problem of particulate matter generation caused by friction between the metal rigid shaft 2 and the proximal bearing 323.

[0048] Please combine Figure 6 , Figure 7 and Figure 9Understood, in this embodiment of the application, the connecting component 3 includes a sleeve 31 with a central through hole 31A, and the proximal end of the rigid shaft 2 has a first shaft segment 21. The outer contour of the first shaft segment 21 is a non-circular structure. For example, the outer contour of the first shaft segment 21 can be an ellipse, a combination of straight lines and arcs (e.g., a D-shape), or an N-sided shape (e.g., a triangle, a quadrilateral, etc.). The central through hole has a first inner hole segment 31A1, and the first shaft segment 21 is at least partially inserted into the first inner hole segment 31A1. The first inner hole segment 31A1 cooperates with the first shaft segment 21 to restrict the circumferential rotation of the sleeve 31 and the rigid shaft 2.

[0049] In this implementation, the rigid shaft 2 and the sleeve 31 are fitted together by inserting into each other. The two are fitted together by a non-circular structure to limit their circumferential rotation. The contact area of ​​the insert fitting is relatively large, and the circumferential limiting of the rigid shaft 2 and the sleeve 31 is not easy to fail. The rigid shaft 2 can rotate synchronously with the sleeve 31. Furthermore, the machining process of the non-circular structure is relatively simple, and the machining cost of the rigid shaft 2 and the sleeve 31 is relatively low.

[0050] Please refer to this again. Figure 6 Figure 9 In one specific embodiment, the outer peripheral wall of the first shaft segment 21 includes at least one first plane 211, which extends parallel to the central axis of the rigid shaft 2. The number of first planes 211 can be one or more. Figure 9 The diagram shows two mutually parallel first planes 211. See also... Figure 7 The inner peripheral wall of the first inner hole section 31A1 includes a second plane 314. The first plane 211 and the second plane 314 cooperate to restrict the circumferential rotation of the sleeve 31 and the rigid shaft 2. In this embodiment, the plane machining is simple and easy to implement.

[0051] Please see Figure 4 and Figure 6 In one specific embodiment, the drive shaft 400 further includes a bushing 4 located at the distal end of the sleeve 31. The distal end of the bushing 4 can abut against the proximal bearing 323 inside the pump head assembly 320 of the duct pump 1000 to limit the extreme position of the rigid shaft 2 moving distally to the duct pump 1000. In this embodiment, the bushing 4 is added to the sleeve 31 and the proximal bearing 323. By abutting against the proximal bearing 323, the extreme position of the rigid shaft 2 moving distally is limited. The position of the rigid shaft 2 in the pump head assembly 320 is controllable, thereby improving the reliability of the operation of the duct pump 1000.

[0052] In one specific embodiment, a limiting part 212 is provided on the shaft segment of the rigid shaft 2 outside the sleeve 31, and the bushing 4 is located between the sleeve 31 and the limiting part 212. The limiting part 212 can be a protruding structure, which can provide axial limiting and blocking for the bushing 4. In this embodiment, the limiting of the bushing 4 along the length direction of the drive shaft 400 is achieved by the limiting part 212 on the rigid shaft 2 and the sleeve 31. This eliminates the need for a separate limiting structure on the proximal bearing 323, and the structure of the proximal bearing 323 can be the same as that in the current technology, which can reduce the modification cost of the current guide pump 1000.

[0053] Please refer to this again. Figure 6 and Figure 9 In one specific embodiment, the rigid shaft 2 may further include a second shaft segment 22, which is a cylindrical segment located distal to the first shaft segment 21. The outer peripheral wall of the first shaft segment 21 includes at least one first plane 211, which is recessed relative to the outer peripheral wall of the second shaft segment 22 toward the central axis of the rigid shaft 2. Correspondingly, the inner peripheral wall of the first inner hole segment 31A1 includes a second plane 314, which cooperates with the first plane 211 to restrict the circumferential rotation of the sleeve 31 and the rigid shaft 2. The distal end of the first plane 211 extends out of the first inner hole segment 31A1 and connects to the outer peripheral wall of the second shaft segment 22 via a stepped surface. The limiting portion 212 is a stepped surface, and the bushing 4 is limited between the sleeve 31 and the stepped surface.

[0054] In this embodiment, the first plane 211 can be formed by machining. Specifically, a cylindrical rigid shaft 2 is first formed, and then a first plane 211 of a predetermined length is machined on the first shaft segment 21 (proximal shaft segment) of the cylindrical rigid shaft 2. A stepped surface is formed between the first plane 211 and the second shaft segment 22 (cylindrical segment). The stepped surface can be a plane perpendicular to the central axis of the rigid shaft 2, or it can be an inclined surface forming an angle with the central axis of the rigid shaft 2. Thus, when the first plane 211 is formed, the limiting part 212 can also be formed simultaneously, simplifying the machining process.

[0055] In one specific embodiment, one of the opposing end faces of the sleeve 31 and the bushing 4 is provided with a protrusion that protrudes axially, and the other is provided with a recess that mates with the protrusion. That is, the end face of the sleeve 31 may be provided with a protrusion 311, and the corresponding end face of the bushing 4 may be provided with a recess 41, such as... Figure 6 As shown; of course, the end face of the sleeve 31 can also be provided with a recess, and the corresponding end face of the bushing 4 can be provided with a protrusion.

[0056] Under the constraint of the protrusions and recesses, the sleeve 31 and the bushing 4 cannot rotate relative to each other in the circumference, or they can only rotate within a small range. This is conducive to the synchronous rotation of the sleeve 31 and the bushing 4 with the rigid shaft 2 and the flexible shaft 1, thereby improving the overall rotational stability of the drive shaft 400.

[0057] The rotational friction between the metal bushing and the proximal bearing can generate metal particles, posing a potential risk to organisms. In this embodiment, the bushing 4 can be made of ceramic material, which can reduce particulate matter and improve the operational safety of the duct pump 1000.

[0058] In one specific embodiment, the connecting assembly 3 further includes at least one pin 32. The sleeve 31 is provided with a first through hole 313 penetrating the peripheral wall of the first inner section 31A1. The first shaft section 21 is provided with a socket 213 coaxially arranged with the first through hole 313. The socket 213 corresponds one-to-one with the pin 32, and the pin 32 is fixedly connected to the inside of the first through hole 313 and the socket 213. During assembly, the first shaft section 21 is first inserted into the inside of the sleeve 31. Then, part of the pin 32 passes through the first through hole 313 from the outside of the sleeve 31 and is inserted into the socket 213, so that the pin 32 is simultaneously located inside the first through hole 313 and the socket 213. In this way, the axial position of the first shaft section 21 and the sleeve 31 is restricted by the pin 32, and the two cannot move relative to each other in the axial direction. Figure 6 As shown, the connecting component 3 includes two pins 32, and correspondingly, the first shaft segment 21 is provided with two sockets 213, which correspond one-to-one with the two pins 32.

[0059] Of course, the number of pins 32 in the connecting assembly 3 is not limited to that described in this application; it can be one, two, or more than three, as long as it can reliably constrain and limit the sleeve 31 and the first shaft segment 21. When there are two or more pins 32, the pins 32 can be located on the same cross-section of the sleeve 31, and of course, the pins 32 can also be arranged at intervals along the axial direction of the sleeve 31.

[0060] To maximize the durability of the first shaft segment 21, the two sockets 213 can be spaced as far apart as possible in the radial direction. Figure 6 The diagram shows that the socket 213 is a notch.

[0061] In one specific embodiment, the outer peripheral wall of the first shaft segment 21 includes two parallel first planes 211 and an arc-shaped wall 214 connecting the two first planes 211. The insertion port 213 is a notch provided on the arc-shaped wall 214, which is isolated from the hollow inner cavity of the rigid shaft 2. In this embodiment, the notch can be as small as possible, so as to reduce the amount of material removed from the first shaft segment 21 while satisfying the insertion and engagement with the pin 32, which is beneficial to improving the service strength of the first shaft segment 21.

[0062] In the above embodiments, the central through hole 31A of the sleeve 31 further includes a second inner hole section 31A2. The distal end of the flexible shaft 1 is located in the second inner hole section 31A2. A bonding agent (not shown in the figure) is filled between the outer peripheral wall of the flexible shaft 1 and the inner peripheral wall of the second inner hole section 31A2. The bonding agent can be solder or adhesive. Under the action of the bonding agent, the flexible shaft 1 and the sleeve 31 are reliably fixed to form an integral structure, and the sleeve 31 can move synchronously with the flexible shaft 1. As described above, the rigid shaft 2 and the sleeve 31 are axially limited by the pin 32 and circumferentially limited by the non-circular structure, so that the flexible shaft 1 can drive the rigid shaft 2 to rotate through the sleeve 31.

[0063] In one embodiment, at least one process through hole 312 may be provided on the peripheral wall of the second inner hole section 31A2 for introducing a bonding agent between the outer peripheral wall of the flexible shaft 1 and the inner peripheral wall of the second inner hole section. That is, after the distal end of the flexible shaft 1 is inserted into the second inner hole section 31A2, the bonding agent can be introduced from the process through hole 312 between the outer peripheral wall of the flexible shaft 1 and the inner peripheral wall of the second inner hole section 31A2 to achieve a reliable connection between the flexible shaft 1 and the sleeve 31.

[0064] As described above, the flexible shaft 1 can be a braided shaft formed by braiding yarns. In one example, the shaft segment of the flexible shaft 1 located inside the second inner hole segment 31A2 can be a braided shaft segment 11. The braided yarns of the braided shaft segment 11 are also filled with a binder, which can be solder or adhesive. The braiding gaps in the braided shaft segment 11 are filled with the binder. When two or more layers of braided yarns form the braided shaft segment 11, at least one layer is filled with binder. For example, the braided shaft segment 11 may only have its outer braided layer filled with binder. Of course, the braided shaft segment 11 may also have all braided layers filled with binder. Filling the braiding gaps of the braided shaft segment 11 with binder helps improve the strength of the braided shaft segment 11 and also enhances the bonding ability between the braided shaft segment 11 and the sleeve 31.

[0065] Specifically, for the flexible shaft 1 located inside the second inner hole section, the shaft section is a braided shaft section 11. The structure in which the braided shaft section 11 is also filled with a binder between the braided filaments can be formed in the following ways: The first forming method is: during forming, the binder is first filled between the braided filaments to form a whole, and then the braided shaft section is inserted into the second inner hole section. The binder is filled between the inner peripheral walls of the braided shaft section and the second inner hole section. In this embodiment, the braided shaft section 11 is filled with a binder before being inserted into the sleeve 31, which is beneficial to fully fill the binder between the braided filaments. Furthermore, the binder filled between the braided filaments and the binder between the braided shaft section and the sleeve 31 can be made of different materials, making the forming flexibility of the drive shaft 400 higher.

[0066] The second forming method is as follows: the shaft section inside the second inner hole section of the flexible shaft 1 is a braided shaft section 11. The braided filaments of the braided shaft section 11 are also filled with a binder. At least one process through hole 312 is provided on the peripheral wall of the second inner hole section. During forming, the binder enters the second inner hole section from the process through hole 312 to fill the braided filaments and the inner peripheral wall between the braided shaft section and the inner hole section.

[0067] In this embodiment, the filling of the bonding agent between the braided yarns and between the braided shaft section 11 and the sleeve 31 is completed in the same process, saving process steps and achieving high molding efficiency.

[0068] The conduit pump 1000 in this application embodiment has the drive shaft 400 of any of the above embodiments, and therefore also has the above-mentioned technical effects of the drive shaft 400.

[0069] For other structural details of the duct pump 1000, please refer to existing technologies; these details will not be elaborated upon here.

[0070] In the description of this application, it should be noted that, in the embodiments of this application, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0071] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, "linking" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. "Fixed connection" refers to a connection where the relative positional relationship remains unchanged after the connection.

[0072] The directional terms used in the embodiments of this application, such as "inner" and "outer," are merely for reference to the directions in the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of this application, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. Furthermore, unless otherwise stated in this application, "multiple" as used in this application refers to two or more.

[0073] In the description of embodiments of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0074] In the embodiments of this application, "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0075] The above are merely preferred embodiments of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A duct pump, characterized in that, Includes the following components: Drive unit (100); The drive shaft (400) includes a flexible shaft (1), a rigid shaft (2) and a connecting assembly (3). The proximal end of the flexible shaft (1) is coupled to the drive device (100), and the distal end of the flexible shaft (1) is connected to the proximal end of the rigid shaft (2) through the connecting assembly (3). The drive device (100) drives the rigid shaft (2) to rotate through the flexible shaft (1). The pump head assembly includes an impeller, a pump housing, and a proximal bearing. The impeller is fitted onto the rigid shaft (2), and the rigid shaft (2) is rotatably supported inside the pump housing by the proximal bearing.

2. The duct pump according to claim 1, characterized in that, The connection position of the flexible shaft (1) and the rigid shaft (2) is located on the proximal side of the proximal bearing; preferably, the connecting assembly (3) is at least partially located on the proximal side of the proximal bearing; Preferably, the connecting assembly (3) is located entirely outside the proximal bearing; or, the connecting assembly (3) is partially located outside the proximal bearing and the remainder is located inside the proximal bearing (323).

3. The duct pump according to claim 1, characterized in that, The connecting assembly (3) includes a sleeve (31) having a central through hole (31A), the proximal end of the rigid shaft (2) having a first shaft segment (21), the outer contour of the first shaft segment (21) being a non-circular structure, the central through hole having a first inner hole segment (31A1), the first shaft segment (21) being at least partially inserted into the first inner hole segment (31A1), the first inner hole segment (31A1) cooperating with the first shaft segment (21) to restrict the circumferential rotation of the sleeve (31) and the rigid shaft (2).

4. The duct pump according to claim 3, characterized in that, The outer peripheral wall of the first shaft segment (21) includes at least one first plane (211) extending parallel to the central axis of the rigid shaft (2), and the inner peripheral wall of the first inner hole segment (31A1) includes a second plane (314). The first plane (211) and the second plane (314) cooperate to restrict the circumferential rotation of the sleeve (31) and the rigid shaft (2).

5. The duct pump according to claim 4, characterized in that, The drive shaft (400) also includes a bushing (4) located at the distal end of the sleeve (31), the distal end of the bushing (4) being able to abut against a proximal bearing inside the pump head assembly of the duct pump to limit the extreme position of the rigid shaft (2) to move distally to the duct pump. Preferably, the rigid shaft (2) is provided with a limiting part (212) on the shaft segment outside the sleeve (31), and the bushing (4) is located between the sleeve (31) and the limiting part.

6. The duct pump according to claim 5, characterized in that, One of the opposite end faces of the sleeve (31) and the bushing (4) is provided with a protrusion, which protrudes axially, and the other is provided with a recess that mates with the protrusion. Alternatively / and, the rigid shaft (2) further includes a second shaft segment (22), the second shaft segment (22) being a cylindrical segment, the second shaft segment (22) being located on the far side of the first shaft segment (21), the outer peripheral wall of the first shaft segment (21) including at least one first plane (211), the first plane (211) being recessed relative to the outer peripheral wall of the second shaft segment (22) toward the central axis of the rigid shaft (2), the inner peripheral wall of the first inner hole segment (31A1) including a second plane (314), the first plane (211) cooperating with the second plane (314) to restrict the circumferential rotation of the sleeve (31) and the rigid shaft (2); the far end of the first plane (211) extends out of the first inner hole segment (31A1) and is connected to the outer peripheral wall of the second shaft segment (22) through a stepped surface, the limiting part being the stepped surface, and the bushing (4) being limited between the sleeve (31) and the stepped surface.

7. The duct pump according to any one of claims 3 to 6, characterized in that, The connecting assembly (3) further includes at least one pin (32), the sleeve (31) is provided with a first through hole (313) penetrating the peripheral wall of the first inner hole section (31A1), the first shaft section (21) is provided with a socket (213) coaxially arranged with the first through hole (313), and the pin (32) is fixedly connected to the inside of the first through hole (313) and the socket (213); Preferably, the outer peripheral wall of the first shaft segment (21) includes two parallel first planes (211) and an arc-shaped wall (214) connecting the two first planes (211). The insertion port (213) is a notch provided on the arc-shaped wall (214), and the notch is isolated from the hollow inner cavity of the rigid shaft (2).

8. The duct pump according to any one of claims 3 to 6, characterized in that, The central through hole also includes a second inner hole section (31A2), the distal end of the flexible shaft (1) is located in the second inner hole section (31A2), and a binder is filled between the outer peripheral wall of the flexible shaft (1) and the inner peripheral wall of the second inner hole section (31A2); Preferably, at least one process through hole (312) is provided on the peripheral wall of the second inner hole section (31A2) for passing the binder between the outer peripheral wall of the flexible shaft (1) and the inner peripheral wall of the second inner hole section (31A2); Preferably, the flexible shaft (1) located inside the second inner hole section (31A2) is a braided shaft section, and the braided filaments of the braided shaft section are also filled with the binder. During molding, the binder is first filled between the braided filaments to form a whole, and then the braided shaft section is inserted into the second inner hole section (31A2), and the binder is filled between the braided shaft section and the inner peripheral wall of the second inner hole section (31A2); or, the flexible shaft (1) located inside the second inner hole section (31A2) is a braided shaft section (11), and the braided filaments of the braided shaft section are also filled with the binder. At least one process through hole is provided on the peripheral wall of the second inner hole section (31A2). During molding, the binder enters the second inner hole section (31A2) through the process through hole to fill between the braided filaments and between the braided shaft section and the inner peripheral wall of the inner hole section.

9. The duct pump according to claim 8, characterized in that, The flexible shaft (1) is located inside the second inner hole section (31A2) in a braided shaft section (11), and the braided yarns of the braided shaft section are also filled with the binder.

10. The duct pump according to any one of claims 1 to 9, characterized in that, The rigid shaft (2) is a non-metallic rigid shaft, and the flexible shaft (1) is a metallic flexible shaft. The flexible shaft (1) is fixedly connected to the connecting assembly (3) by welding, and the rigid shaft (2) is connected to the connecting assembly (3) by non-welding. Preferably, the hard shaft (2) is a ceramic material hard shaft; Alternatively / and, the bushing (4) is a ceramic material bushing.

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