A flat-end basket automatic locking mechanism and basket catheter

Abstract

The application discloses a flat-head net basket automatic locking mechanism and a net basket catheter, and relates to the technical field of medical devices.The locking mechanism comprises a special-shaped tube, an embedded tube, a bolt and an elastic locking part.The embedded tube is inserted into the special-shaped tube at one end, and a gap for clamping the distal end of a nickel-titanium sheet is arranged between the other end of the special-shaped tube and the embedded tube.The embedded tube is fixedly connected to the other end of the special-shaped tube by adhesion.The elastic locking part is arranged inside the embedded tube.The bolt is used for being inserted into the embedded tube and extruding the elastic locking part.After the end of the nickel-titanium sheet of the net basket is inserted between the special-shaped tube and the embedded tube, the bolt is inserted into the embedded tube.During the insertion process, the end of the bolt slides the sliding pin shaft by extruding the inclined surface, so that the sliding pin shaft slides along the inclined groove and compresses the elastic part, thereby facilitating the sliding pin shaft to generate radial extrusion force on the bolt by the rebound force of the elastic part, facilitating the locking of the bolt, and ensuring the locking of the end of the nickel-titanium sheet.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a flat-end basket automatic locking mechanism and a basket catheter. BACKGROUND

[0002] In recent years, catheter therapy has been widely used in the treatment of various diseases, such as patients' heart or intravenous, once the catheter reaches the intended site, the corresponding technology can be performed to the treatment. And the distal end of the catheter used in the prior art is designed in various forms, and the flat-end basket catheter is one of the forms.

[0003] The basket of the basket catheter in the prior art is generally cut from a nickel-titanium wire or a nickel-titanium sheet, and the nickel-titanium wire or the nickel-titanium sheet at the distal end of the basket is generally fixed by gluing through a metal column at the head end.

[0004] The nickel-titanium sheet fixing structure of the existing flat-end basket has the following disadvantages: after the nickel-titanium sheet of the existing basket catheter is fixed by gluing, it is easy to cause the glue to fail due to immersion in blood during use, which may cause the parts to fall off into the human body, thereby having a great impact on life and health. SUMMARY

[0005] The present application aims to provide a flat-end basket automatic locking mechanism and a basket catheter to solve the technical problem that the end of the flat-end basket net nickel-titanium sheet is easily fixed by gluing in the prior art, which may cause failure and falling off, and may cause danger to the patient.

[0006] The technical problem to be solved by the present application can be solved by the following technical scheme:

[0007] A flat-end basket automatic locking mechanism, comprising:

[0008] A special-shaped tube and an embedded tube, one end of the embedded tube is inserted into the special-shaped tube, and a gap for clamping the distal end of the nickel-titanium sheet is provided between the other end of the special-shaped tube and the embedded tube, and the other end is fixedly connected with the embedded tube;

[0009] A latch and an elastic locking member, the elastic locking member is arranged inside the embedded tube, the latch is used for inserting into the embedded tube and pressing the elastic locking member, the elastic locking member is used for generating a radial pressing force on the latch inserted into the embedded tube, and one end of the latch and the inner wall of the special-shaped tube jointly clamp the distal end of the nickel-titanium sheet.

[0010] Preferably, the special-shaped tube comprises a thick-walled section and a thin-walled section, the inner diameter of the thick-walled section is equal to the outer diameter of the embedded tube, and the thick-walled section is fixedly connected with the embedded tube, the inner diameter of the thin-walled section is smaller than the outer diameter of the embedded tube, and the edge of the side of the thin-walled section away from the thick-walled section exceeds the edge of the embedded tube.

[0011] Preferably, the plug-in part comprises a plug rod and a pressing head, the plug rod is used for inserting into the built-in tube, the pressing head is fixedly connected to one end of the plug rod, and the pressing head is matched with the profiled tube to clamp the distal end of the nitinol sheet.

[0012] Preferably, the pressing head comprises a positioning plug, the diameter of the positioning plug is greater than that of the plug rod, the outer diameter of the positioning plug is equal to the inner diameter of the built-in tube, and an outer convex body is arranged on the side of the positioning plug away from the plug rod, the outer diameter of the outer convex body is greater than the outer diameter of the built-in tube, and the outer diameter of the outer convex body is less than the inner diameter of the thin-walled section.

[0013] Preferably, the elastic locking mechanism comprises a bevel groove, a sliding pin shaft, an elastic member and a positioning block, the positioning block is fixedly arranged in the built-in tube, the bevel groove is arranged on the inner wall of the built-in tube, the sliding pin shaft is slidingly connected in the bevel groove, and the elastic member is arranged between the sliding pin shaft and the positioning block.

[0014] Preferably, the plug-in part is provided with a pressing bevel matched with the sliding pin shaft at one end of the plug-in part used for inserting into the built-in tube.

[0015] Preferably, a spiral groove is arranged on the outer wall of the plug-in part, and a clamping groove distributed along the radial direction of the plug-in part is arranged on the side of the spiral groove away from the pressing bevel, and the clamping groove and the spiral groove are matched with the sliding pin shaft.

[0016] Preferably, the elastic member is a profiled spiral spring, the elastic member comprises a large-circle part and a small-circle part, the large-circle part and the small-circle part are alternately distributed, the large-circle part is attached to the inner wall of the built-in tube, and the small-circle part is attached to the outer wall of the plug-in part.

[0017] Preferably, a through hole for the plug-in part to pass through is arranged on the positioning block, and a tapered guide groove concentrically distributed with the through hole is arranged on the side of the positioning block close to the elastic member, and the tapered guide groove facilitates guiding the end of the plug-in part to insert into the through hole.

[0018] The present application has the following beneficial effects:

[0019] 1. After the end of the nitinol sheet of the net basket is inserted between the profiled tube and the built-in tube, the plug-in part is inserted into the built-in tube, after the plug-in part is inserted in place, the pressing head on the plug-in part clamps the end of the nitinol sheet together with the thin-walled section of the profiled tube through the outer convex body arranged thereon, and during the insertion of the plug-in part, the end thereof slides the sliding pin shaft through the pressing bevel, so that the sliding pin shaft slides along the bevel groove and compresses the elastic member, so as to facilitate the elastic member to generate a radial extrusion force on the plug-in part through the resilience of the elastic member, so as to facilitate locking the plug-in part, thereby ensuring that the end of the nitinol sheet is locked and falling off is avoided.

[0020] 2、The spiral groove and the radially distributed clamping groove on the latch can effectively prevent the sliding pin shaft and the latch from slipping, that is, prevent the latch from sliding out due to overall vibration, movement, jolt and the like to cause adverse phenomena.

[0021] 3、The elastic member is a special-shaped spiral spring, which includes large circle portions and small circle portions in an alternating manner, which is beneficial to reduce the twist of the elastic member caused by compression, leading to uneven elasticity and affecting the locking of the latch; and the phenomenon of uneven self-locking stress is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a schematic diagram of the overall structure of the present application;

[0023] Figure 2 is Figure 1 is an enlarged structure schematic diagram of position A in the figure;

[0024] Figure 3 is Figure 1 is an enlarged structure schematic diagram of position B in the figure;

[0025] Figure 4 is a structure schematic diagram of the relative position distribution of the inclined groove and the built-in tube in the present application;

[0026] Figure 5 is a structure schematic diagram of the sliding pin shaft and the inclined groove in the present application;

[0027] Figure 6 is a structure schematic diagram of the latch in the present application;

[0028] Figure 7 is a state schematic diagram of the latch in the present application before being inserted into the built-in tube;

[0029] Figure 8 is a state schematic diagram of the end of the latch in the present application when the extrusion bevel starts to contact the sliding pin shaft;

[0030] Figure 9 is a state schematic diagram of the latch in the present application when the sliding pin shaft is extruded by the extrusion bevel.

[0031] BRIEF DESCRIPTION OF DRAWINGS

[0032] 1, Nickel titanium sheet; 2, PEEK tube; 3, restraint ring; 4, inner support sleeve; 5, special-shaped tube; 51, thick wall section; 52, thin wall section; 6, built-in tube; 7, balloon; 8, latch; 81, positioning plug; 82, insertion rod; 83, spiral groove; 84, clamping groove; 85, extrusion bevel; 86, outer convex body; 9, sliding pin shaft; 10, elastic member; 11, positioning stopper; 12, inclined groove; 13, perforation; 14, conical guide groove. DETAILED DESCRIPTION

[0033] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0034] like Figures 1-9 As shown, an automatic locking mechanism for a flat-headed basket is used to lock the end of the nickel-titanium sheet 1 in the basket structure of a medical flat-headed basket catheter. The basket structure includes multiple circumferentially distributed nickel-titanium sheets 1, and both ends of the nickel-titanium sheets 1 need to be locked. The locking mechanism includes a special-shaped tube 5, an internal tube 6, a pin 8, and an elastic locking element. One end of the internal tube 6 is inserted into the special-shaped tube 5, and a gap is provided between one end of the special-shaped tube 5 and the internal tube 6 for locking the distal end of the nickel-titanium sheet 1. The other end is fitted and fixedly connected to the internal tube 6.

[0035] The elastic locking element is located inside the built-in tube 6. The pin 8 is inserted into the built-in tube 6 and squeezes the elastic locking element. The elastic locking element is used to generate radial squeezing force on the pin 8 inserted into the built-in tube 6 to prevent the inserted pin 8 from coming out of the built-in tube 6. One end of the pin 8 and the inner wall of the shaped tube 5 clamp the far end of the nickel-titanium sheet 1 together.

[0036] In some specific implementations, the shaped tube 5 includes a thick-walled section 51 and a thin-walled section 52. The inner diameter of the thick-walled section 51 is equal to the outer diameter of the built-in tube 6, and the thick-walled section 51 is fixedly connected to the built-in tube 6. The inner diameter of the thin-walled section 52 is smaller than the outer diameter of the built-in tube 6, and the edge of the thin-walled section 52 away from the thick-walled section 51 extends beyond the edge of the built-in tube 6, that is, the two are not aligned. The end of the built-in tube 6 is located inside the thin-walled section 52. This facilitates the existence of a gap between the end of the built-in tube 6 and the thin-walled section 52 for inserting the distal end of the nickel-titanium sheet 1. At the same time, since the edge of the built-in tube 6 is shorter than the edge of the thin-walled section 52, it is convenient to press the nickel-titanium sheet 1 onto the thin-walled section 52 by the end of the pin 8.

[0037] In some specific implementation schemes, refer to Figure 6 As shown, the insert 8 includes an insert rod 82 and a pressing head. The insert rod 82 is used to insert into the built-in tube 6, and the pressing head is fixedly connected to one end of the insert rod 82. Both are cylindrical. The pressing head cooperates with the shaped tube 5 to clamp the distal end of the nickel-titanium sheet 1.

[0038] The extrusion head includes a positioning plug 81, the diameter of which is larger than the diameter of the insertion rod 82. The outer diameter of the positioning plug 81 is equal to the inner diameter of the built-in tube 6, and the two fit together. An outer protrusion 86 is provided on the side of the positioning plug 81 away from the insertion rod 82. The outer diameter of the outer protrusion 86 is larger than the outer diameter of the built-in tube 6, which can be slightly larger. The specific size can be set based on the thickness of the nickel-titanium sheet 1. The outer diameter of the outer protrusion 86 is smaller than the inner diameter of the thin-walled section 52.

[0039] After the distal end of the nickel-titanium sheet 1 is inserted between the thin-walled section 52 of the shaped tube 5 and the inner tube 6 to achieve initial positioning, the pin 8 is inserted into the inner tube 6. The positioning plug 81 of the pin 8 is inserted into the inner tube 6, and the protrusion 86 on the positioning plug 81 stops against the end of the inner tube 6. Since the outer diameter of the protrusion 86 is larger than the outer diameter of the inner tube 6 and smaller than the inner diameter of the thin-walled section 52 of the shaped tube 5, it can exert a squeezing effect on the inserted nickel-titanium sheet 1. The nickel-titanium sheet 1 can be squeezed and deformed to a certain extent, so that it is easy to be pressed by the protrusion 86.

[0040] In some specific implementation schemes, refer to Figure 7 As shown, the elastic locking mechanism includes a sloping groove 12, a sliding pin 9, an elastic element 10, and a positioning block 11. The positioning block 11 is fixedly installed inside the inner tube 6. The sloping groove 12 is opened on the inner wall of the inner tube 6, and two sloping grooves are provided, distributed in pairs on both sides of the inner tube 6. The sliding pin 9 is slidably connected in the sloping groove 12 and spans between the two sloping grooves 12. The elastic element 10 is installed between the sliding pin 9 and the positioning block 11. It should be noted that the initial position of the sliding pin 9 is close to the position of the central axis of the inner tube 6.

[0041] When the pin 8 is inserted into the inner tube 6, the end of the pin 8 contacts and squeezes the sliding pin 9, causing the sliding pin 9 to slide along the inclined groove 12. The sliding pin 9 also compresses the elastic element 10. When the pin 8 is inserted to the position of the positioning block 11, it is properly inserted. At this time, due to the rebound force of the elastic element 10, the sliding pin 9 pushes the sliding pin 9, thereby causing the sliding pin 9 to generate radial extrusion force on the pin 8, thus locking the pin 8 and preventing it from coming off during the use of the basket guide tube.

[0042] In some specific embodiments, the end of the pin 8 that is inserted into the built-in tube 6 is provided with a pressing bevel 85 that cooperates with the sliding pin 9. During the insertion of the pin 8, the pressing bevel 85 at its end contacts the sliding pin 9 and presses it, so as to facilitate the pressing of the sliding pin 9 to slide along the inclined groove 12.

[0043] In some specific implementations, to prevent the sliding pin 9 from slipping off the pin 8, a spiral groove 83 is provided on the outer wall of the pin 8, and a slot 84 distributed radially along the pin 8 is provided on the side of the spiral groove 83 away from the extrusion slope 85. Both the slot 84 and the spiral groove 83 cooperate with the sliding pin 9. During the process of the pin 8 being inserted into the inner tube 6, and after the sliding pin 9 is pressed along the inclined groove 12 by the extrusion slope 85, as the pin 8 continues to go deeper, the spiral groove 83 comes into contact with the sliding pin 9. At this time, in order to avoid obstruction, the pin 8 can be rotated to keep moving forward until the sliding pin 9 is locked in the slot 84. By setting the spiral groove 83 and the slot 84, the pin 8 and the sliding pin 9 can be better contacted, preventing slippage. At the same time, the slot 84 at the end of the spiral groove 83 can prevent the pin 8 from slipping out due to overall vibration, movement, bumps, etc., causing adverse phenomena.

[0044] In some specific implementation schemes, refer to Figure 7 As shown, the elastic element 10 is an irregularly shaped helical spring. The elastic element 10 includes a large coil part and a small coil part, which are distributed alternately. The large coil part is attached to the inner wall of the built-in tube 6, and the small coil part is attached to the outer wall of the pin 8. This design helps to reduce the torsion of the elastic element 10 caused by compression, which would lead to uneven elastic force and thus affect the locking of the pin 8; and avoid the phenomenon of uneven self-locking force.

[0045] In some specific implementations, the positioning block 11 has a through hole 13 for the pin 8 to pass through, and the positioning block 11 has a conical guide groove 14 concentrically distributed with the through hole 13 on the side near the elastic member 10. The conical guide groove 14 facilitates the insertion of the end of the pin 8 into the through hole 13.

[0046] In other specific implementation schemes, refer to Figure 3 As shown, the automatic locking mechanism of the flat-head basket also includes a fixing mechanism for fixing the proximal end of the nickel-titanium sheet 1. The fixing mechanism includes a binding ring 3 and an inner support sleeve 4. The inner support sleeve 4 is inserted inside the binding ring 3, and the proximal end of the nickel-titanium sheet 1 is inserted between the binding ring 3 and the inner support sleeve 4. The outer diameter of one end of the inner support sleeve 4 gradually increases, while the outer diameter of the other end remains unchanged. The end with the changing diameter clamps and locks with the binding ring 3 on the outside, preventing the nickel-titanium sheet 1 from being pulled out.

[0047] It should be noted that epoxy glue can be injected between the restraining ring 3 and the inner support sleeve 4 for further fixation, and epoxy glue can also be injected into the gap between the shaped tube 5 and the inner tube 6 for further fixation to ensure that the nickel-titanium sheet 1 will not fall off.

[0048] A net basket guide tube may include the automatic locking mechanism of any of the above embodiments, and also includes a balloon 7 and a PEEK tube 2. The balloon 7 is fixedly sleeved on the outside of the inner tube 6 and is located on one side of the shaped tube 5. The PEEK tube 2 is a polyetheretherketone material tube, which is close to the inside of the inner tube 6 and abuts against the positioning block 11. The PEEK tube 2 slides through the inner support sleeve 4, that is, the inner support sleeve 4 can slide relative to the PEEK tube 2, thereby facilitating the storage or opening of the flat-head net basket composed of nickel-titanium sheets 1.

[0049] To facilitate understanding of the embodiments of this solution by those skilled in the art, the working principle of this solution will now be briefly explained in conjunction with specific application scenarios:

[0050] First, the proximal end of the nickel-titanium sheet 1 that makes up the basket structure is inserted circumferentially between the binding ring 3 and the inner support sleeve 4, and the end of the inner support sleeve 4 with a variable diameter forms a clamping lock with the binding ring 3; then the distal end of the nickel-titanium sheet 1 is inserted into the gap between the inner tube 6 and the special-shaped tube 5.

[0051] Then, the pin 8 is inserted into the inner tube 6. The positioning plug 81 of the pin 8 is inserted into the inner tube 6, and the protrusion 86 on the positioning plug 81 stops at the end of the inner tube 6. Since the outer diameter of the protrusion 86 is larger than the outer diameter of the inner tube 6 and smaller than the inner diameter of the thin-walled section 52 of the special tube 5, it can exert a squeezing effect on the inserted nickel-titanium sheet 1. The nickel-titanium sheet 1 can be squeezed and deformed to a certain extent, so that it is easy to be pressed by the protrusion 86.

[0052] Furthermore, during the insertion of the pin 8 into the built-in tube 6, the end of the pin 8 contacts and presses the sliding pin 9 by the pressing inclined surface 85, causing the sliding pin 9 to slide along the inclined groove 12. The sliding pin 9 also compresses the elastic element 10. When the pin 8 is inserted to the position of the positioning block 11, it is properly inserted. At this time, due to the rebound force of the elastic element 10, the sliding pin 9 pushes the sliding pin 9, thereby causing the sliding pin 9 to generate radial pressing force on the pin 8, thus automatically locking the pin 8 and preventing it from detaching during the use of the basket guide tube, thereby preventing the end of the nickel-titanium sheet 1 from falling off.

[0053] Furthermore, when the pin 8 is inserted into the built-in tube 6 and is in place, the sliding pin 9 is precisely engaged in the slot 84. By setting the spiral groove 83 and the slot 84, the pin 8 and the sliding pin 9 can be better contacted to prevent slippage. At the same time, the slot 84 at the end of the spiral groove 83 can prevent the pin 8 from slipping out due to overall vibration, movement, bumps, etc., causing adverse phenomena.

[0054] Meanwhile, the elastic element 10 is an irregularly shaped helical spring, composed of alternating large and small coils, which helps to reduce the twisting caused by compression of the elastic element 10, thus reducing uneven elastic force and affecting the locking of the pin 8; and avoiding uneven self-locking force.

[0055] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. An automatic locking mechanism for a flat-headed wire basket, characterized in that, include: The irregular tube (5) and the built-in tube (6) are provided. One end of the built-in tube (6) is inserted into the irregular tube (5), and a gap is provided between one end of the irregular tube (5) and the built-in tube (6) for holding the far end of the nickel-titanium sheet (1). The other end is attached and fixedly connected to the built-in tube (6). The pin (8) and the elastic locking member are arranged inside the built-in tube (6). The pin (8) is used to insert into the built-in tube (6) and squeeze the elastic locking member. The elastic locking member is used to generate radial extrusion force on the pin (8) inserted into the built-in tube (6). One end of the pin (8) and the inner wall of the shaped tube (5) clamp the distal end of the nickel-titanium sheet (1).

2. The automatic locking mechanism for a flat-headed wire basket according to claim 1, characterized in that, The shaped tube (5) includes a thick-walled section (51) and a thin-walled section (52). The inner diameter of the thick-walled section (51) is equal to the outer diameter of the built-in tube (6), and the thick-walled section (51) is fixedly connected to the built-in tube (6). The inner diameter of the thin-walled section (52) is greater than the outer diameter of the built-in tube (6), and the edge of the thin-walled section (52) away from the thick-walled section (51) extends beyond the edge of the built-in tube (6).

3. The automatic locking mechanism for a flat-headed wire basket according to claim 2, characterized in that, The pin (8) includes a pin (82) and a pressing head. The pin (82) is used to insert into the built-in tube (6). The pressing head is fixedly connected to one end of the pin (82). The pressing head cooperates with the shaped tube (5) to clamp the distal end of the nickel-titanium sheet (1).

4. The automatic locking mechanism for a flat-headed wire basket according to claim 3, characterized in that, The extrusion head includes a positioning plug (81), the diameter of which is greater than the diameter of the insertion rod (82). The outer diameter of the positioning plug (81) is equal to the inner diameter of the built-in tube (6). An external protrusion (86) is provided on the side of the positioning plug (81) away from the insertion rod (82). The outer diameter of the external protrusion (86) is greater than the outer diameter of the built-in tube (6), and the outer diameter of the external protrusion (86) is smaller than the inner diameter of the thin-walled section (52).

5. The automatic locking mechanism for a flat-headed wire basket according to claim 1, characterized in that, The elastic locking component includes a groove (12), a sliding pin (9), an elastic element (10), and a positioning block (11). The positioning block (11) is fixedly installed inside the inner tube (6). The groove (12) is opened on the inner wall of the inner tube (6). The sliding pin (9) is slidably connected inside the groove (12). The elastic element (10) is installed between the sliding pin (9) and the positioning block (11).

6. The automatic locking mechanism for a flat-headed wire basket according to claim 5, characterized in that, The pin (8) is provided with a pressing bevel (85) at one end for insertion into the inner tube (6) to cooperate with the sliding pin (9).

7. The automatic locking mechanism for a flat-headed wire basket according to claim 5, characterized in that, The outer wall of the pin (8) is provided with a spiral groove (83), and a slot (84) is provided on the side of the spiral groove (83) away from the extrusion slope (85) along the radial distribution of the pin (8). Both the slot (84) and the spiral groove (83) are engaged with the sliding pin (9).

8. The automatic locking mechanism for a flat-headed wire basket according to claim 5, characterized in that, The elastic element (10) is a non-circular helical spring. The elastic element (10) includes a large coil portion and a small coil portion, which are distributed alternately. The large coil portion is attached to the inner wall of the built-in tube (6), and the small coil portion is attached to the outer wall of the pin (8).

9. The automatic locking mechanism for a flat-headed wire basket according to claim 5, characterized in that, The positioning block (11) has a through hole (13) for the pin (8) to pass through, and a conical guide groove (14) is provided on the side of the positioning block (11) near the elastic member (10) and is concentrically distributed with the through hole (13). The conical guide groove (14) is used to guide the end of the pin (8) to be inserted into the through hole (13).

10. A basket guide tube, characterized in that, The invention includes an automatic locking mechanism for a flat-headed basket as described in any one of claims 1 to 9.

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