Ball head locking mechanism of basket catheter and basket catheter

Abstract

The present invention relates to the technical field of medical instruments. Disclosed are a ball head locking mechanism of a basket catheter and a basket catheter. The ball head locking mechanism comprises a ball head screw, a ball head thread insert and a restraining ring, wherein the ball head screw is threadedly connected to the inner side of the ball head thread insert, and the outer wall of the ball head thread insert is of a slope structure. In the present invention, the ball head screw and the ball head thread insert which are in threaded fit are screwed together, and end portions of nickel-titanium sheets of a basket structure are effectively pressed against the slope structure by means of the restraining ring, thereby achieving effective locking and avoiding the use of glue bonding to reduce the risk of detachment. In addition, the ball head thread insert can further be in the form of a combination of an expansion ring and a compression thread insert. When the ball head screw and the compression thread insert are rotated relative to each other and tightened, the ball screw and the compression thread insert can also jointly compress the expansion ring, so that the expansion ring expands outwards to press against the nickel-titanium sheets, thereby further assisting in locking the nickel-titanium sheets, and ensuring the locking effect.

Description

A ball-head locking mechanism for a net basket guide tube and the net basket guide tube. Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a ball head locking mechanism for a basket catheter and the basket catheter itself. Background Technology

[0002] In recent years, catheter therapy has been widely used to treat a variety of diseases, such as those affecting the heart or veins. Once the catheter reaches the intended site, treatment can be performed using appropriate techniques. Furthermore, the distal ends of catheters used in current technologies are designed in various different shapes, with basket catheters being one such example.

[0003] In the prior art, the basket structure of the basket guide tube is generally made of nickel-titanium wire or nickel-titanium sheet cut from it. The nickel-titanium sheet at the far end of the basket is glued and fixed by the metal column at the head end.

[0004] The existing nickel-titanium sheet fixing structure for net basket guide tubes has the following drawback: The nickel-titanium sheets in existing net basket guide tubes are fixed by adhesive application. However, because these sheets are immersed in blood during use, the adhesive is prone to failure, leading to parts loosening and entering the body, thus posing a significant threat to health. Therefore, net basket guide tube products require a safer method for distal fixation of the net basket. Summary of the Invention

[0005] The purpose of this invention is to provide a ball-head locking mechanism for a basket catheter and a basket catheter, in order to solve the technical problem that the nickel-titanium sheet end of the basket catheter is easily lost or detached due to adhesive bonding in the prior art, which poses a danger to patients.

[0006] The technical problem to be solved by the present invention can be achieved through the following technical solution: A ball head locking mechanism for a net basket guide tube, comprising: a ball head screw and a ball head sleeve, wherein the ball head screw is threadedly connected to the inner side of the ball head sleeve, and the outer wall of the ball head sleeve is a ramp structure; a restraining ring, wherein the restraining ring is disposed on the outer side of the ball head screw, and the restraining ring cooperates with the ramp structure to lock the end of the nickel-titanium sheet; as a further embodiment of the present invention: the ball head screw is a hollow structure, the ball head screw includes a screw part and a ball head fixedly disposed at one end of the screw part, one side of the restraining ring is fixedly connected to the ball head of the ball head screw, and a gap is provided between the restraining ring and the ramp structure for accommodating the end of the nickel-titanium sheet.

[0007] As a further aspect of the present invention: the ball head sleeve includes an expansion ring and a compression sleeve, the ball head screw is threadedly connected to the compression sleeve, the expansion ring is fitted between the ball head of the ball head screw and the compression sleeve, and the ball head of the ball head screw and the compression sleeve move towards each other to compress the expansion ring.

[0008] As a further aspect of the present invention, the expansion ring is made of medical-grade silicone.

[0009] As a further aspect of the present invention: the expansion ring is provided with an inverted ramp shape on the side near the extrusion sleeve, and the extrusion sleeve is provided with an arc chamfer on the side near the expansion ring that engages with the inverted ramp shape.

[0010] As a further aspect of the present invention: after the screw portion of the ball head screw is threadedly assembled with the ball head screw sleeve, the distance between position D between the restraining ring and the ramp structure is 0.15mm, with a positive and negative error of 0.02mm.

[0011] As a further aspect of the present invention: the included angle between the two waists of the ball-end threaded sleeve cross section is set to 6°, with a positive and negative error of 0.3°.

[0012] As a further aspect of the present invention: the outer wall of the ball-end threaded sleeve is circumferentially distributed with a plurality of grooves for positioning nickel-titanium sheets.

[0013] As a further aspect of the present invention, the groove depth for positioning the nickel-titanium sheet is no greater than 0.05 mm.

[0014] The beneficial effects of the present invention are as follows: 1. The present invention uses a ball head screw and a ball head sleeve with threaded engagement to screw together, and relies on the binding ring to effectively press the end of the nickel-titanium sheet of the basket structure onto the slope structure, thereby achieving effective locking and avoiding the risk of falling off when using glue.

[0015] 2. The ball head screw sleeve of the present invention can also be in the form of a combination of an expansion ring and a compression screw sleeve. When the ball head screw and the compression screw sleeve are rotated and tightened relative to each other, the ball head screw and the compression screw sleeve can also work together to compress the expansion ring, causing the expansion ring to expand outward, which makes it easier to press the nickel-titanium sheet, further assisting in locking the nickel-titanium sheet and ensuring the locking effect.

[0016] 3. The minimum spacing between the ramp structure and the restraint ring of this invention is designed based on the thickness of the nickel-iron sheet end of the net basket structure on the market, so as to avoid the nickel-titanium sheet from breaking due to excessive tightness. At the same time, the angle of the ramp structure is set to 6°, which is suitable for the distribution and locking of the nickel-titanium sheet. Furthermore, the design of the ramp structure makes the nickel-titanium sheet that makes up the basket structure evenly distributed, and avoids the nickel-titanium sheet from concave when tightened, which would affect the balloon of the existing net basket conduit. Attached Figure Description

[0017] The invention will now be further described with reference to the accompanying drawings.

[0018] Figure 1 is a schematic diagram of the overall structure of the present invention; Figure 2 is an enlarged schematic diagram of point A in Figure 1; Figure 3 is a schematic diagram of the structure of the ball end threaded sleeve implemented by the expansion ring and the extrusion threaded sleeve in the present invention; Figure 4 is an enlarged schematic diagram of point B in Figure 3; Figure 5 is a schematic diagram of the structure of the present invention in which the nickel-titanium sheet does not concave after tightening; Figure 6 is a schematic diagram of the structure of the present invention in which the nickel-titanium sheet concave after tightening; Figure 7 is a schematic diagram of the structure of the expansion ring in the present invention; Figure 8 is a schematic diagram of the structure of the extrusion threaded sleeve in the present invention; Figure 9 is a schematic diagram of the structure of the ball end threaded sleeve in the present invention; Figure 10 is an enlarged schematic diagram of point C in Figure 2.

[0019] In the diagram: 1. Guide wire tube; 2. PEEK tube; 3. Balloon; 4. Nickel-titanium sheet; 5. Restraint ring; 6. Ball end cap; 7. Ball end screw; 8. Expansion ring; 9. Extrusion sleeve; 10. Ramp structure; 11. Inverted ramp shape; 12. Rounded chamfer. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] As shown in Figures 1-10, a ball-head locking mechanism for a net basket conduit is used to lock the ends of the nickel-titanium sheets 4 of the net basket structure in the net basket conduit. The net basket structure includes multiple circumferentially distributed nickel-titanium sheets 4. The ball-head locking mechanism includes a ball-head screw 7, a ball-head sleeve 6, and a restraining ring 5. The ball-head screw 7 is inserted into the inner side of the ball-head sleeve 6 and is threadedly connected to the ball-head sleeve 6. The ball-head screw 7 and the ball-head sleeve 6 are made of 316 stainless steel. The outer wall of the ball-head sleeve 6 is a ramp structure 10, which allows relative displacement between the ball-head screw 7 and the ball-head sleeve 6 by relative rotation. The restraining ring 5 is located on the outer side of the ball-head screw 7 and cooperates with the ramp structure 10 to lock the ends of the nickel-titanium sheets 4 of the net basket structure. Specifically, the binding ring 5 and the ball head screw 7 are configured such that the ball head screw 7 is a hollow structure, including a screw part and a ball head fixedly disposed at one end of the screw part. One side of the binding ring 5 is fixedly connected to the ball head of the ball head screw 7, and there is a gap between the inner wall of the binding ring 5 and the ramp structure 10 to accommodate the end of the nickel-titanium sheet 4. By rotating the ball head screw 7 relative to the ball head thread sleeve 6, the binding ring 5 is driven to fix and press the end of the nickel-titanium sheet 4 onto the ball head thread sleeve 6.

[0022] Furthermore, due to the slope structure 10, when the nickel-titanium sheet 4 is tightened, the nickel-iron sheet 4 can be prevented from concave as shown in Figure 6, and the state shown in Figure 5 can be achieved, effectively preventing the nickel-iron sheet 4 from contacting and wearing with the balloon 3 set in the basket guide tube in this state.

[0023] In some specific embodiments, to further lock the nickel-titanium sheet 4 of the basket structure, as shown in Figures 3 and 4, the ball end cap 6 includes an expansion ring 8 and a compression sleeve 9. The ball end screw 7 is threadedly connected to the compression sleeve 9. In this embodiment, the outer wall of the compression sleeve 9 is set as a ramp structure 10. The expansion ring 8 is positioned between the ball head of the ball end screw 7 and the compression sleeve 9, and the inner ring of the expansion ring 8 is attached to the screw portion of the ball end screw 7. The expansion ring 8 is made of medical silicone. The ball head of the ball end screw 7 and the compression sleeve 9 move towards each other to compress the expansion ring 8, causing it to deform and expand outward. When the nickel-titanium sheet 4 is locked by the combined action of the ramp structure 10 and the restraint ring 5, the outwardly expanding expansion ring 8 can further assist in the compression and locking, ensuring effective locking.

[0024] In some other specific embodiments, in order to facilitate the ball head screw 7 and the compression sleeve 9 to effectively compress the expansion ring 8, as shown in Figures 4, 7 and 8, the expansion ring 8 is provided with an inverted ramp shape 11 on the side near the compression sleeve 9, and the compression sleeve 9 is provided with an arc chamfer 12 that mates with the inverted ramp shape 11 on the side near the expansion ring 8. By providing the inverted ramp shape 11 and the arc chamfer 12, it is convenient for the compression sleeve 9 to compress the expansion ring 8 to expand outward.

[0025] In some specific implementation schemes, since the thickness of the nickel-titanium sheet 4 in most commercially available basket structures is 0.2mm with a tolerance of ±0.03mm, and the nickel-titanium sheet 4 can be deformed to a certain extent by compression, after the screw part of the ball head screw 7 is threaded together with the ball head screw sleeve 6 and tightened, the distance at position D between the restraining ring 5 and the ramp structure 10 is 0.15mm with a tolerance of ±0.02mm. Position D here is the minimum distance between the restraining ring 5 and the ramp structure 10, which is also the optimal distance, as shown in Figure 10. In this way, the restraining ring 5 and the ramp structure 10 can work together to compress the nickel-titanium sheet 4, causing it to deform to a certain extent, thereby achieving the purpose of "locking" and tightening without causing the nickel-titanium sheet 4 to break due to excessive tightness.

[0026] Furthermore, in order to effectively clamp the nickel-titanium sheet 4 and form a uniform basket structure after clamping, as shown in Figure 9, since the outer wall of the ball-head threaded sleeve 6 is set as a slope structure 10, the cross section of the ball-head threaded sleeve 6 is a trapezoidal surface. The included angle between the two sides of the cross section of the ball-head threaded sleeve 6 is set to 6°, with a positive and negative error of 0.3°. In this way, when the basket guide tube is used up and needs to be tightened from the opened spherical shape into a loose shape and put into the sheath, this angle setting is conducive to the nickel-titanium sheet forming a straight state for storage.

[0027] It should be noted that when the angle of the ramp structure 10 was set to 1° during the test, the nickel-titanium sheet 4 of the net basket structure was unevenly distributed, and the nickel-titanium sheet 4 was concave when tightened, which could easily affect the balloon 3, as shown in Figure 6.

[0028] In some specific implementations, the outer wall of the ball-end threaded sleeve 6 has multiple grooves distributed circumferentially for positioning the nickel-titanium sheet 4, which facilitates the direct positioning and snapping of the end of the nickel-titanium sheet 4 into the corresponding groove during installation, thus enabling quick positioning and installation.

[0029] It should be noted that the depth of the groove is no more than 0.05mm, so as to avoid the groove being too deep and affecting the fixing effect of the nickel-titanium sheet 4.

[0030] A basket catheter may include the ball head locking mechanism of any of the above embodiments, and further include a guide wire tube 1, a balloon 3 and a PEEK tube 2, wherein the PEEK tube 2 is a polyetheretherketone (PEEK) material tube, the guide wire tube 1 is inserted inside the PEEK tube 2 and the two are fixedly installed, and the guide wire tube 1 can slide relative to the original sheath tube, the end of the PEEK tube 2 is fixedly connected to the inside of the ball head screw 7, and the balloon 3 is sleeved on the outside of the PEEK tube 2 and is fixed in position relative to the PEEK tube 2.

[0031] To facilitate understanding of the embodiments of this solution by those skilled in the art, the working principle of this solution is briefly explained in conjunction with a specific application scenario: First, the nickel-titanium sheets 4 of the basket structure are circumferentially distributed on the ramp structure 10 outside the ball head screw sleeve 6. Then, the ball head screw sleeve 6 and the threaded ball head screw 7 rotate relative to each other. The ball head screw 7 causes the restraining ring 5 to squeeze the end of the nickel-titanium sheet 4 on the ramp structure 10, thereby pressing and locking it.

[0032] Since most of the nickel-titanium sheets 4 in the market are 0.2mm thick with a tolerance of ±0.03mm, and the nickel-titanium sheets 4 can be deformed to a certain extent, the distance between the side of the binding ring 5 away from the ball head of the ball head screw 7 and the ramp structure 10 is set to 0.15mm with a tolerance of ±0.02mm, which is the minimum distance between the binding ring 5 and the ramp structure 10. When the two ends of the screw part of the ball head screw 7 are respectively flush with the two ends of the ball head screw sleeve 6, the binding ring 5 and the ramp structure 10 work together to compress the nickel-titanium sheet 4, causing it to deform to a certain extent, thereby achieving the purpose of "locking" and tightening without causing the nickel-titanium sheet 4 to break due to excessive tightness. At the same time, the included angle between the ramp structures 10 on both sides of the ball head screw sleeve 6 is set to 6° with a tolerance of ±0.3°, which can effectively prevent the nickel-titanium sheet 4 from concave and facilitate the uniform distribution of the nickel-titanium sheet 4.

[0033] The ball head threaded sleeve 6 can also be a combination of an expansion ring 8 and a compression threaded sleeve 9. The ball head screw 7 and the compression threaded sleeve 9 are threaded together. The two move towards each other to compress the expansion ring 8, causing it to deform and expand outward. When the nickel-titanium sheet 4 is locked by the combined action of the ramp structure 10 and the binding ring 5, the expansion ring 8, which expands outward, can further assist in the compression and locking to ensure effective locking.

[0034] The foregoing has described several embodiments of the present invention in detail, but these embodiments are not limited thereto and should not be considered as limiting the scope of the invention. All equivalent variations and improvements made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A ball-head locking mechanism for a net basket guide tube, characterized in that, include: Ball head screw (7) and ball head sleeve (6), wherein the ball head screw (7) is threaded to the inner side of the ball head sleeve (6), and the outer wall of the ball head sleeve (6) is a slope structure (10); A restraint ring (5) is provided on the outside of the ball head screw (7). The restraint ring (5) cooperates with the ramp structure (10) to lock the end of the nickel-titanium sheet (4).

2. The ball-head locking mechanism for a net basket guide tube according to claim 1, characterized in that, The ball head screw (7) has a hollow structure and includes a screw part and a ball head fixedly disposed at one end of the screw part. One side of the binding ring (5) is fixedly connected to the ball head of the ball head screw (7), and a gap is provided between the binding ring (5) and the ramp structure (10) for accommodating the end of the nickel-titanium sheet (4).

3. The ball-head locking mechanism for a net basket guide tube according to claim 2, characterized in that, The ball head threaded sleeve (6) includes an expansion ring (8) and a compression threaded sleeve (9). The ball head screw (7) is threadedly connected to the compression threaded sleeve (9). The expansion ring (8) is fitted between the ball head of the ball head screw (7) and the compression threaded sleeve (9). The ball head of the ball head screw (7) and the compression threaded sleeve (9) move towards each other to compress the expansion ring (8).

4. The ball-head locking mechanism for a net basket guide tube according to claim 3, characterized in that: The expansion ring (8) is made of medical-grade silicone.

5. The ball-head locking mechanism for a net basket guide tube according to claim 3, characterized in that, The expansion ring (8) has an inverted ramp shape (11) on the side near the extrusion sleeve (9), and the extrusion sleeve (9) has an arc chamfer (12) that mates with the inverted ramp shape (11) on the side near the expansion ring (8).

6. The ball-head locking mechanism for a basket guide tube according to claim 2, characterized in that, After the screw part of the ball head screw (7) is threaded together with the ball head screw sleeve (6), the distance between the D position of the restraining ring (5) and the ramp structure (10) is 0.15mm, and the positive and negative error is 0.02mm.

7. The ball head locking mechanism for a net basket guide tube according to claim 1, characterized in that, The included angle between the two sides of the cross section of the ball-head threaded sleeve (6) is set to 6°, with a positive and negative error of 0.3°.

8. The ball head locking mechanism for a net basket guide tube according to claim 1, characterized in that, The outer wall of the ball-head threaded sleeve (6) has multiple grooves distributed circumferentially for positioning the nickel-titanium sheet (4).

9. The ball-head locking mechanism for a basket guide tube according to claim 8, characterized in that, The groove depth for positioning the nickel-titanium sheet (4) is no greater than 0.05 mm.

10. A basket guide tube, characterized in that, Includes a ball head locking mechanism for a net basket guide tube as described in any one of claims 1 to 9.

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