A wire fixing device for an adjustable bending sheath tube

Abstract

The present application relates to a wire fixing device for an adjustable bending sheath tube, comprising a pull ring and a wire, wherein the pull ring is arranged at the distal end of the adjustable bending sheath tube and is fixedly connected to the adjustable bending sheath tube, a wire receiving groove is arranged on the tube wall of the pull ring, the distal end of the wire is placed and fixed in the wire receiving groove, and the proximal end of the wire extends out of the body. The wire fixing device avoids the problems of stress concentration, easy falling off and easy breaking of welding points existing in direct welding, and improves product safety.

Description

Technical Field

[0001] The present application belongs to the field of medical devices, and specifically relates to a wire fixing device for an adjustable curved sheath tube. Background Art

[0002] In interventional treatment, catheters are the most commonly used treatment consumables. Due to the complex structure of the human body, catheters need to meet a certain bending angle after entering the human body in order to better treat diseases. The current technical means is to achieve the bending of the distal part of the catheter by pulling the wire. The main principle is: the distal end of the pull wire is directly fixed to the pull ring by welding, and the proximal end of the pull wire is connected to the control system. The pull wire is pulled by the control system to transfer force to the pull wire. The pull wire moves relatively in the axial direction of the catheter, and the force is transferred to the pull ring set on the catheter through the welding point, thereby driving the elastic section of the distal part of the catheter to bend and realize the bending of the catheter.

[0003] When the distal end of the catheter adopts an adjustable bend design, the reliability of the fixed connection between the pull ring and the pull wire determines the success or failure of the product. Since the front end of the catheter needs to be bent repeatedly, that is to say, the place where the pull wire and the pull ring are fixed will constantly change the stress condition of the stress point with the repeated bending of the catheter, which requires the fixing point of the pull wire and the catheter to withstand a certain fatigue strength. At present, the most common way to fix the pull wire and the pull ring is welding. In addition, there are other fixing methods such as gluing and hot melt coating. When welding is used, the welding point is small, the welding process requirements are high, and stress concentration is easy to form at the welding point. When the traction force is large or the catheter is repeatedly bent, the welding point is prone to fatigue fracture, which leads to problems such as easy failure at the welding point; gluing has problems such as stress concentration, easy detachment of glue, and insufficient connection strength; hot melt coating has problems such as insufficient connection strength, easy detachment of the pull wire, and severe damage to the catheter structure.

[0004] Chinese patent CN 103706017 B discloses an adjustable bending sheath tube, including a tube body, a traction mechanism and a fixed connection mechanism; the traction mechanism includes an anchoring ring and a traction wire; the anchoring ring is coaxially embedded in the distal elastic section of the tube body; the traction wire is arranged in the side wall of the tube body and extends along the axial direction of the tube body, and the traction wire includes a first section and a second section connected to each other, the first section is connected to the fixed connection mechanism near the proximal end of the tube body, and the second section hooks the anchoring ring. Because the traction wire hooks the anchoring ring, the force point between the anchoring ring and the traction wire is the hooking part, which is easily subjected to shear force during the bending adjustment, causing the traction wire to break. At the same time, because the traction wire is outside the anchoring ring, the diameter of the bending adjustment sheath tube at this point is additionally increased. Summary of the invention

[0005] The purpose of the present invention is to overcome the existing technical limitations. In view of the problems existing in the products in the prior art field, such as stress concentration in welding of connection points, low connection strength, easy cutting of the pull wire at the surrounding fixed points, and increased diameter of the distal end of the adjustable bending sheath tube, a pull wire fixing device for an adjustable bending sheath tube is designed.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A pull wire fixing device for an adjustable bending sheath tube comprises a pull ring and a pull wire, wherein the pull ring is arranged at the distal end of the adjustable bending sheath tube and is fixedly connected to the adjustable bending sheath tube, a pull wire accommodating groove is arranged on the tube wall of the pull ring, the distal end of the pull wire is placed and fixed in the pull wire accommodating groove, and the proximal end of the pull wire extends out of the body.

[0008] The purpose of the present invention can be further achieved by the following technical solutions:

[0009] In one embodiment, the pull wire accommodating groove is divided into two parts, the first part is a straight groove longitudinally arranged along the inner wall of the pull ring, which can only accommodate two pull wires side by side, and the second part is an annular groove arranged along the circumferential direction of the inner wall of the pull ring, which can only accommodate one pull wire. The distal end of the pull wire enters from the straight groove, and ends at the straight groove after circling along the annular groove. The proximal end of the pull wire extends out of the body, and the main body of the pull wire is placed in the pull wire channel. The pull wire channel is a cylindrical structure, and its inner diameter is slightly larger than the outer diameter of the pull wire, that is, the pull wire can be accommodated in the pull wire channel. The gap between the pull wire and the annular groove and the straight groove is filled with glue or solder, and the outer surface of the glue or solder is flush with the inner wall of the pull ring.

[0010] In one embodiment, the pull wire accommodating groove is divided into two parts, the first part is a straight groove longitudinally arranged along the outer wall of the pull ring, which can only accommodate two pull wires side by side, and the second part is an annular groove arranged along the circumferential direction of the outer wall of the pull ring, which can only accommodate one pull wire. The distal end of the pull wire enters from the straight groove, and ends at the straight groove after circling along the annular groove. The proximal end of the pull wire extends out of the body, and the main body of the pull wire is placed in the pull wire channel. The pull wire channel is a cylindrical structure, and its inner diameter is slightly larger than the outer diameter of the pull wire, that is, the pull wire can be accommodated in the pull wire channel. The gap between the pull wire and the annular groove and the straight groove is filled with glue or solder, and the outer surface of the glue or solder is flush with the outer wall of the pull ring.

[0011] In one embodiment, the pull ring is composed of a pull ring seat and a pull ring cover, the pull ring cover is provided with an annular protrusion and a rectangular protrusion, the pull ring seat is provided with an annular groove matching the shape of the annular protrusion and a straight groove matching the shape of the rectangular protrusion, and the pull ring cover fixes the distal end of the pull wire in the annular groove and the straight groove provided on the pull ring seat through the annular protrusion and the rectangular protrusion.

[0012] In one embodiment, a hole is provided inside the pull ring wall, and the hole diameter gradually increases along the longitudinal direction. When the pull wire enters the hole from the direction of the small aperture, the pull wire gathers into a ball on the large aperture side of the hole, and the gap between the hole and the pull wire is filled with glue or soldering to form a fixed connection.

[0013] In one embodiment, the pull wire accommodating groove is distributed in a stepped shape along the outer wall of the pull ring, the pull wire is embedded in the pull ring along the stepped pull wire accommodating groove, the gap between the pull wire and the pull wire accommodating groove is filled with glue or solder, and the outer surface of the glue or the solder is flush with the outer wall of the pull ring.

[0014] In one embodiment, the diameter of the pull ring is 0.15-4.0 mm, and the wall thickness of the pull ring is 0.06-0.3 mm.

[0015] In one embodiment, the pull ring is made of heavy metals such as stainless steel, platinum, gold, tungsten, tantalum, or alloys thereof.

[0016] In one embodiment, the pull wire is a round or flat metal wire with a diameter of 0.05-0.25 mm, and the metal wire is made of stainless steel wire, tungsten alloy steel wire, cobalt-chromium alloy steel wire, nickel-titanium alloy steel wire, and the like.

[0017] Compared with the prior art, the advantages of the present invention are:

[0018] 1. The main innovation of the present invention is that the pull ring adopts a wire receiving groove structure, and the pull wire and the pull ring are indirectly fixed by filling the gap between the pull wire and the wire receiving groove with glue or solder, thereby avoiding the stress concentration existing in the direct welding method, and the problems of easy falling off and breaking of the solder joints, thereby improving the safety of the product.

[0019] 2. The main innovation of the present invention is that it makes full use of the friction force when the pull wire and the pull wire receiving groove are in contact. This force plays a role in fixing the pull wire and the pull ring to a certain extent. In addition, it is fixed by welding or filling the gap with glue, which has a double fixing effect. Compared with ordinary welding methods, the fixed connection between the pull ring and the pull wire is more reliable, thereby improving product safety.

[0020] 3. The main innovation of the present invention is that it makes full use of the wall thickness space of the pull ring, embeds the pull wire in the pull wire accommodating groove of the pull ring, fixes the pull ring and the pull wire without increasing the extra size, has no obvious effect on the thickness of the side wall of the tube body, will not increase the outer diameter of the delivery catheter, reduces the surgical incision, and reduces the surgical risk. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the wire fixing device of the present invention.

[0022] Figure 2 It is a schematic structural diagram of a pull ring in the first embodiment of the pull wire fixing device of the present invention.

[0023] Figure 3 It is a cross-sectional view of the pull ring in the first embodiment of the pull wire fixing device of the present invention.

[0024] Figure 4 It is a schematic structural diagram of a pull ring in the second embodiment of the pull wire fixing device of the present invention.

[0025] Figure 5 It is a cross-sectional view of a pull ring in the second embodiment of the pull wire fixing device of the present invention.

[0026] Figure 6 It is a schematic structural diagram of a pull ring seat in the third embodiment of the pull wire fixing device of the present invention.

[0027] Figure 7 Schematic diagram of the structure of the pull ring cover in the third embodiment of the pull wire fixing device of the present invention.

[0028] Figure 8 Schematic diagram of the structure of the pull ring in the fourth embodiment of the pull wire fixing device of the present invention.

[0029] Fig. 9 Schematic diagram of the structure of the pull ring in the fifth embodiment of the pull wire fixing device of the present invention.

[0030] Fig.10 It is a schematic diagram of the distal end of the pull wire and the pull ring connecting portion in the fifth embodiment of the pull wire fixing device of the present invention. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0032] Embodiment 1

[0033] The present invention is mainly applied to the field of adjustable bending sheath, and relates to a novel wire fixing device for an adjustable bending sheath tube. Figure 1As shown, the pull wire fixing device includes a pull ring 100 and a pull wire 120. The pull ring 100 is arranged at the distal end of the adjustable bending sheath tube and is fixedly connected to the adjustable bending sheath tube. A pull wire receiving groove is arranged on the tube wall of the pull ring 100. The distal end 121 of the pull wire 120 is placed and fixed in the pull wire receiving groove, and the proximal end 123 of the pull wire 120 extends out of the body. The main body 122 of the pull wire 120 is placed in the pull wire channel 110.

[0034] like Figure 2 and Figure 3 As shown, the wire accommodating groove is divided into two parts, the first part is a straight groove 102 arranged longitudinally along the inner wall of the pull ring 100, which can only accommodate two pull wires 120 arranged side by side, and the second part is an annular groove 101 arranged along the circumferential direction of the inner wall of the pull ring 100, which can only accommodate one pull wire. The distal end 121 of the pull wire 120 enters from the straight groove 102, and ends at the straight groove 102 after circling along the annular groove 101. The proximal end 123 of the pull wire 120 extends out of the body, and the main body 122 of the pull wire 120 is placed in the pull wire channel 110. The pull wire channel 110 is a cylindrical structure, preferably a cylindrical structure, and its inner diameter is slightly larger than the outer diameter of the pull wire. The gap between the pull wire 120 and the annular groove 101 and the straight groove 102 is filled with glue or solder, and the outer surface of the glue or solder is flush with the inner wall of the pull ring 100.

[0035] In one embodiment, the diameter of the pull ring is 0.15-4.0 mm, and the wall thickness of the pull ring is 0.06-0.3 mm. The pull ring is made of heavy metals such as stainless steel, platinum, gold, tungsten, tantalum, or alloys thereof.

[0036] In one embodiment, the pull wire is a round or flat metal wire with a diameter of 0.05-0.25 mm, and the metal wire is made of stainless steel wire, tungsten alloy steel wire, cobalt-chromium alloy steel wire, nickel-titanium alloy steel wire, and the like.

[0037] Embodiment 2

[0038] like Figure 1 , Figure 4 and Figure 5As shown, the present embodiment is different from the first embodiment in that the wire holding groove is divided into two parts, the first part is a straight groove 102 longitudinally arranged along the outer wall of the pull ring 100, which can only accommodate two side-by-side pull wires 120, and the second part is an annular groove 101 arranged along the circumferential direction of the outer wall of the pull ring 100, which can only accommodate one pull wire 120. The distal end 121 of the pull wire 120 enters from the straight groove 102, and ends at the straight groove 102 after circling along the annular groove 101. The proximal end 123 of the pull wire 120 extends out of the body, and the main body 122 of the pull wire 120 is placed in the pull wire channel 110, which is a cylindrical structure with an inner diameter slightly larger than the outer diameter of the pull wire. The gap between the pull wire 120 and the annular groove 101 and the straight groove 102 is filled with glue or solder, and the outer surface of the glue or solder is flush with the outer wall of the pull ring 100.

[0039] Embodiment 3

[0040] like Figure 6 and Figure 7 As shown, the present embodiment is different from the first embodiment in that: the pull ring 100 is composed of a pull ring seat 104 and a pull ring cover 105, an annular protrusion 106 and a rectangular protrusion 107 are arranged on the pull ring cover 105, an annular groove 101 matching the shape of the annular protrusion 106 and a straight groove 102 matching the shape of the rectangular protrusion 107 are arranged on the pull ring seat 104, and the pull ring cover 105 fixes the distal end 121 of the pull wire 120 in the annular groove 101 and the straight groove 102 arranged on the pull ring seat 104 through the annular protrusion 106 and the rectangular protrusion 107. That is, after the distal end 121 of the pull wire 120 enters along the straight groove 102, it goes around along the inner wall of the annular groove 101 and is placed on the inner wall of the straight groove 102, and the pull ring cover 105 is covered, and the pull wire 120 comes out from the bottom of the rectangular protrusion 107 of the pull ring cover 105. The gaps between the annular groove 101 and the straight groove 102 and the pull wire 120 are filled with solder or glue.

[0041] Embodiment 4

[0042] like Figure 8 As shown, this embodiment is different from the first embodiment in that a hole 103 is provided inside the wall of the pull ring 100, and the hole 103 gradually increases in diameter in the longitudinal direction to form a skirt-like structure. When the pull wire 120 enters the hole 103 from the direction of the small aperture, the pull wire 120 gathers together on the large aperture side of the hole 103, and the gap between the hole 103 and the pull wire 120 is filled with glue or soldering to form a fixed connection.

[0043] Embodiment 5

[0044] like Fig. 9 and Fig.10 As shown, the present embodiment is different from the first embodiment in that the wire accommodating groove is distributed in a stepped shape along the outer wall of the pull ring 100, and the wire accommodating groove is divided into two parts. The first part is a straight groove 102 arranged longitudinally along the outer wall of the pull ring 100. The number of the straight grooves is five, namely 102a, 102b, 102c, 102d, and 102e, which can only accommodate one wire 120. The second part is an arc groove 101 arranged along the circumferential direction of the outer wall of the pull ring 100, which can only accommodate one wire 120. The distal end 121 of the pull wire 120 is embedded in the pull ring 100 along the stepped wire accommodating groove, and the gap between the pull wire 120 and the wire accommodating groove is filled with glue or solder, and the outer surface of the glue or solder is flush with the outer wall of the pull ring.

[0045] Fig.10 The distal end 121 of the pull wire 120 is inserted into the straight groove 102a, passes through the arc groove 101, is inserted into the straight groove 102b, and then is inserted into the straight groove 102c, passes through the arc groove 101, and then is inserted into the straight groove 102d, and then is inserted into the straight groove 102e. Finally, the pull wire is inserted into and terminates in the arc groove 101.

[0046] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A pull wire fixing device for an adjustable bending sheath tube, comprising a pull ring and a pull wire, characterized in that: The pull ring is arranged at the distal end of the adjustable bending sheath tube and is fixedly connected to the adjustable bending sheath tube. A pull wire receiving groove is arranged on the outer wall of the pull ring. The distal end of the pull wire is placed and fixed in the pull wire receiving groove, and the proximal end of the pull wire extends out of the body. The pull wire accommodating groove is distributed in a stepped shape along the outer wall of the pull ring, and the pull wire is embedded in the pull ring along the stepped pull wire accommodating groove; The pull wire accommodating groove is divided into two parts, the first part is a plurality of straight grooves arranged longitudinally along the outer wall of the pull ring, each of which can only accommodate one pull wire, and the second part is an arc groove arranged along the circumferential direction of the outer wall of the pull ring, each of which can only accommodate one pull wire; The main body of the pull wire is placed in a pull wire channel, and the pull wire channel is in a cylindrical structure, and the inner diameter of the pull wire is slightly larger than the outer diameter of the pull wire.

2. The wire fixing device for the adjustable bending sheath tube according to claim 1, characterized in that: The gap between the pull wire and the pull wire accommodating groove is filled with glue or solder, and the outer surface of the glue or solder is flush with the outer wall of the pull ring.

3. The wire fixing device for the adjustable bending sheath tube according to claim 1, characterized in that: The diameter of the pull ring is 0.15-4.0 mm, the wall thickness of the pull ring is 0.06-0.3 mm, and the pull wire is a round or flat metal wire.

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