Manufacturing method of balloon dilatation catheter and balloon dilatation catheter

Abstract

The invention discloses a manufacturing method of a balloon dilatation catheter and the balloon dilatation catheter, and the manufacturing method of the balloon dilatation catheter comprises the following steps: expanding one end of the catheter to form an expansion part; the near end of the balloon is arranged in the expansion part; and heating the outer periphery of the dilation part so that the dilation part is connected with the balloon in the dilation part. According to the embodiment of the invention, the catheter which is positioned on the outer part and has a relatively thick wall is firstly melted, and then the balloon which is positioned on the inner part and has a relatively thin wall is melted, so that the balloon can be connected with the catheter after being slightly melted, and the attenuation of the thickness and the performance of the balloon due to the influence of excessive radiation of heat is avoided; the use stability of the balloon is improved, and the blasting risk of the balloon in the use process is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of medical catheters, in particular to a method for manufacturing a balloon dilatation catheter and the balloon dilatation catheter. Background Art

[0002] Neurointerventional devices are mainly used for neurointerventional diagnosis or treatment of cerebrovascular diseases. They are high-value consumables with high technology and value content. Balloon dilatation catheter is one of the main devices for non-invasive angioplasty surgery including neurointerventional treatment.

[0003] In the manufacture of balloon dilatation catheters, the connection between the catheter and the balloon must be strictly sealed and have sufficient strength to withstand fluid pressure. The balloon and the catheter can be connected by welding or bonding.

[0004] Using highly viscous materials to bond catheters and balloons can effectively avoid defects such as material deformation and stress concentration. However, this method relies heavily on manual operation and has a low degree of automation. The introduction of new mass will increase the profile (outer diameter profile) of the connection point. The rigidity of the glue will increase after UV curing, which will damage the flexibility of the distal end of the balloon catheter product.

[0005] The welding method is to input a large amount of heat into the place where the catheter and the balloon are connected, so that the two are fused together.

[0006] In the prior art, the proximal end of the balloon dilatation catheter formed by welding is prone to bursting during use. Once the balloon ruptures in the body, the risk of surgical operation will be greatly increased. Summary of the invention

[0007] The purpose of the present invention is to provide a method for manufacturing a balloon dilatation catheter to solve the deficiencies in the prior art, which can reduce the risk of balloon explosion during use and greatly improve the safety of surgical operations.

[0008] The method for manufacturing a balloon dilatation catheter provided by the present invention comprises the following steps:

[0009] enlarging one end of the catheter to form a dilation;

[0010] placing the proximal end of the balloon within the expansion portion;

[0011] Heat is applied to the periphery of the expansion portion to connect the expansion portion with the balloon located inside the expansion portion.

[0012] Furthermore, the balloon comprises a balloon body, a proximal pin located at the proximal end of the balloon body, and a distal pin located at the distal end of the balloon body;

[0013] Before the periphery of the expansion portion is heated, at least a portion of the proximal pins are located in the expansion portion, and the periphery of the expansion portion is heated to connect the expansion portion and the proximal pins.

[0014] Furthermore, the catheter and the balloon are made of the same material and are both formed of a thermoplastic polymer material, and the thermoplastic polymer material is a block polyetheramide resin.

[0015] Furthermore, “heating the periphery of the expansion portion to connect the expansion portion to the proximal pin” includes:

[0016] A heat shrink tube is disposed outside the catheter, and at least a portion of the heat shrink tube covers the expansion portion;

[0017] The heat shrinkable tube located outside the expansion part is heated to make the conduit become a viscous flow state, and the heat shrinkable tube shrinks under the heat to apply pressure outside the expansion part.

[0018] Furthermore, “heating the periphery of the expansion portion to connect the expansion portion to the proximal pin” includes:

[0019] Synchronously rotating the catheter and the balloon along the circumference of the catheter;

[0020] Laser welding is performed on the periphery of the expansion portion, wherein the welding power ranges from 1 to 1.2 W and the welding time ranges from 5 to 7 s.

[0021] Furthermore, during the laser welding process, the rotation speed of the catheter and the balloon is 800-1000 rpm, and the welding heat is not less than 6 joules.

[0022] Further, “enlarging one end of the catheter to form a dilated portion” comprises the following steps:

[0023] heating the conical die;

[0024] One end of the catheter is sleeved on the heated conical mold, and the one end of the catheter is deformed by heat to form the expansion portion.

[0025] Further, “placing the proximal end of the balloon in the expansion portion” comprises the following steps:

[0026] The catheter and the balloon are sheathed outside the core shaft;

[0027] The balloon and / or the catheter is moved along the axial direction of the core shaft so that the proximal end of the balloon extends into the expansion part.

[0028] Furthermore, before “arranging the catheter and the balloon outside the core shaft”, it also includes:

[0029] A mandrel coating is coated on the outside of the mandrel, and the mandrel coating is at least one of a polytetrafluoroethylene coating and a polyparaxylene coating.

[0030] Another embodiment of the present invention further discloses a balloon dilatation catheter, which is manufactured using the manufacturing method.

[0031] Compared with the prior art, the manufacturing method of the balloon dilatation catheter of the present invention overcomes technical prejudice, and realizes the stable connection between the catheter and the balloon by not changing the catheter model and the balloon structure without affecting the internal flow space of the catheter. Specifically, the tube mouth of the catheter is enlarged by expanding the opening, so that the proximal end of the balloon can be placed in the expansion part, and in the process of connecting the catheter and the balloon, the catheter with a relatively thick wall is heated, and then the heat is transferred to the balloon with a relatively thin wall located inside the catheter, so that the balloon can be fixedly connected with the catheter in a molten state or when it is not molten.

[0032] Compared with the balloon being set outside the catheter, the balloon is first heated and melted during the heating process, and then the heat is conducted to the catheter. During the entire process of fixed connection, the balloon is subjected to relatively large amounts of heat and has a high degree of melting, resulting in uneven thickness of some parts of the balloon after re-solidification, and the risk of thinning in some areas, which also causes performance degradation and ultimately leads to the rupture of the balloon during use.

[0033] The embodiment of the present invention effectively solves the above-mentioned problems by placing the catheter outside the balloon with minimal changes to the existing process, improves the stability of the balloon, reduces the risk of balloon explosion during use, and greatly improves the safety of surgical operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic flow chart of a method for manufacturing a balloon dilatation catheter disclosed in an embodiment of the present invention;

[0035] Figure 2 It is a schematic diagram of the positioning relationship between the catheter and the balloon before welding in the method for manufacturing the balloon dilatation catheter disclosed in the embodiment of the present invention;

[0036] Figure 3 It is a schematic structural diagram of a catheter and a balloon after welding in a method for manufacturing a balloon dilatation catheter disclosed in an embodiment of the present invention;

[0037] Explanation of the reference numerals: 1-balloon, 11-balloon body, 12-proximal pin, 2-catheter, 21-expansion portion, 3-core shaft, 4-heat shrink tube. DETAILED DESCRIPTION

[0038] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, but should not be construed as limiting the present invention.

[0039] It should be understood that, unless otherwise clearly specified and limited, in the description of the present invention, the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, the connection can be a direct connection or an indirect connection through an intermediate medium, and can be a fixed connection, a movable connection, a detachable connection, or an integral connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0040] For the convenience of description, the perspective of the instrument operator during the use of the balloon dilatation catheter is used as a reference, and the end away from the operator is defined as the distal end, and the end close to the operator is defined as the proximal end.

[0041] Balloon dilatation catheters have been widely used in the diagnosis and treatment of cardiovascular diseases. Currently, balloon dilatation catheters are basically divided into four types: rapid exchange type, integral exchange type, fixed guidewire balloon, and perfusion balloon.

[0042] The inventor has found that the balloon dilatation catheter currently formed by welding is prone to rupture because in the existing welding process, the end of the balloon 1 is sleeved outside the catheter 2, and then the catheter 2 and the balloon 1 are connected by laser heating and melting. Since the wall thickness of the balloon 1 is generally smaller than the wall thickness of the catheter 2, during the laser welding process, the end of the balloon 1 is heated first and then the catheter covering the inside of the balloon 1 is heated. When heated by the laser, the end of the balloon 1 is heated first, and the heat is transferred to the catheter while melting. The balloon 1 is easily overheated, which easily causes the end of the balloon 1 to be punctured or thinned, and finally causes the formed balloon 1 to rupture when subjected to a large fluid pressure.

[0043] The present invention aims to provide a method for combining a balloon 1 and a catheter 2 together to solve the above technical problems.

[0044] The balloon 1 is a balloon designed by the present invention, and other balloons in the prior art may also be used. The catheter 2 may be a catheter designed by the present invention, and other catheters in the prior art may also be used.

[0045] The following will focus on how to combine the balloon 1 and the catheter 2 together.

[0046] like Figure 1 As shown, the manufacturing method of the balloon dilatation catheter disclosed in the present invention comprises the following steps:

[0047] S1: expanding one end of the catheter 2 to form an expansion portion 21;

[0048] S2: placing the proximal end of the balloon 1 in the expansion portion 21;

[0049] S3: Heat the periphery of the expansion part 21 to connect the expansion part 21 with the balloon 1 located inside the expansion part 21.

[0050] In the prior art, for the convenience of use, the size of the catheter 2 is generally limited, and the size of the balloon 1 is designed according to the size of the catheter 2. The part of the balloon 1 that is combined with the catheter 2 is the joint part of the balloon 1. The joint part of the balloon 1 and the catheter 2 can be combined in two ways, one is that the joint part is sleeved outside the catheter 2, and the other is that the joint part is penetrated in the catheter 2, that is, the catheter 2 is sleeved outside the joint part. In a specific embodiment, the joint part can be the pin of the balloon 1. In the design process, under the premise of the catheter 2 of the same outer diameter size, the wall thickness of the joint part is increased by setting the joint part to penetrate in the catheter 2. Because, compared with the balloon 1 being sleeved outside the catheter 2, when the balloon 1 is penetrated in the catheter 2 of the same size, the outer diameter size of the joint part must be reduced, but in order to ensure that the main part of the balloon 1 has a sufficiently large outer diameter, the amount of material used in the molding process of the balloon 1 in the above two ways must be the same. Therefore, for the same amount of material, when the outer diameter of the joint of the balloon 1 is smaller, the wall thickness formed will inevitably increase, and the increase in wall thickness will lead to an increase in its stiffness, thereby having an adverse effect on the performance of the balloon catheter such as pushing ability, flexibility, passability, maximum contour, and re-embraceability.

[0051] At the same time, in order to ensure that there is a flow channel with a sufficiently large cross-sectional size in the catheter 2, the balloon 1 is generally set outside the catheter 2. If the joint of the balloon 1 is set in the catheter 2, then under the premise of the catheter 2 of the same size, the part of the balloon 1 that penetrates into the catheter 2 will occupy more channel space in the catheter 2, thereby affecting the use of the catheter 2. Therefore, the outer diameter of the joint of the balloon 1 is generally set to be larger than the outer diameter of the catheter 2.

[0052] The manufacturing method of the present invention overcomes technical prejudices and achieves a stable connection between the catheter 2 and the balloon 1 without changing the model of the catheter 2 and the structure of the balloon 1 without changing the flow space. Specifically, the orifice of the catheter 2 is enlarged by expanding the opening, so that the proximal end of the balloon 1 can be placed in the expansion portion 21. During the heating process, the catheter 2, which is located outside and has a thick wall, is heated and melted. The catheter 2 is heated and melted and conducts heat to the balloon 1, which is located inside and has a thin wall. The proximal end of the balloon 1 is heated and melted and connected to the catheter 2. After cooling, the catheter 2 and the balloon 1 are fixedly connected. It should be noted that during the combination process, the balloon 1 may not melt, but the catheter 2 is connected to the balloon 1 during the cooling process after melting.

[0053] In the present invention, during the process of connecting the catheter 2 and the balloon 1, the catheter 2 located on the outside and with a relatively thick wall is melted first, and then the balloon 1 located on the inside and with a relatively thin wall is melted, so that the balloon 1 can be connected to the catheter 2 after being slightly melted, thereby avoiding the attenuation of the thickness and performance of the balloon 1 due to excessive heating, improving the use stability of the balloon 1, reducing the probability of the balloon 1 exploding during use, and greatly improving the safety of the surgical operation.

[0054] The specific type of the balloon dilatation catheter in the present invention is not further limited, and it can be a rapid exchange balloon dilatation catheter, a coaxial integral exchange balloon dilatation catheter, or other types of balloon dilatation catheters.

[0055] In the present invention, the balloon 1 generally includes a balloon body 11, a proximal pin 12 located at the proximal end of the balloon body 11, and a distal pin located at the distal end of the balloon body 11. It can be understood that the proximal pin 12 and the distal pin are arranged on opposite sides of the balloon body 11. The proximal pin 12 is used to connect with the catheter 2.

[0056] Before the periphery of the expansion portion 21 is heated, at least part of the proximal pins 12 are located in the expansion portion 21 . The periphery of the expansion portion 21 is heated to connect the expansion portion 21 with the proximal pins 12 located in the expansion portion 21 .

[0057] In the present invention, the materials of the balloon 1 and the catheter 2 are determined according to the specific product requirements. The catheter 2 is generally made of thermoplastic polymer materials. Pebax can be used for balloon dilatation catheter products in the field of neurointervention, TPU can be used for occlusion balloon catheter products, and PA can be used for balloon dilatation catheter products in the field of coronary / peripheral intervention. The specific material of the balloon 1 can be a silicone balloon, a latex balloon or a TPU balloon.

[0058] In the present invention, in order to better connect the catheter 2 and the balloon 1, the catheter 2 and the balloon 1 are made of the same material, and both the catheter 2 and the balloon 1 are made of thermoplastic polymer materials.

[0059] Specifically, the materials of the balloon 1 and the catheter 2 are both segmented polyetheramide resin (pebax), and the commonly used grades are 6333SA 01MED, 7033SA 01MED, 7233SA 01MED, 7433SA01MED. The balloon 1 and the catheter 2 of the present invention are specifically 7033SA 01MED.

[0060] Of course, in other embodiments, the materials of the catheter 2 and the balloon 1 may be different. Specifically, the glass transition temperature of the material of the catheter 2 may be higher than the glass transition temperature of the material of the balloon 1, so that the catheter 2 and the balloon 1 can be melted synchronously when the periphery of the catheter 2 is heated.

[0061] In the present invention, since the catheter 2 is made of a thermoplastic polymer material, the catheter 2 changes from a stable glass state to a viscous flow state after being heated, so as to be combined with the balloon 1 which is also in a viscous flow state after being heated, so that the two are finally fixed together after cooling. Figure 3 It is a schematic diagram of the structure after connection. After the catheter 2 and the balloon 1 are combined, the two are fused together, and there is no obvious fault at the position where the two are connected.

[0062] In the above embodiment, both the catheter 2 and the balloon 1 are in a non-glass state after being heated. In other embodiments, only the catheter 2 may be in a viscous flow state after being heated, and the viscous flow catheter 2 is connected to the glassy balloon 1 after being cooled.

[0063] In step S1, the expansion portion 21 is formed to facilitate the placement of the proximal end of the balloon 1 therein.

[0064] The present invention preferably uses a heated mold to form the expansion portion 21. It can be understood that the expansion portion 21 is actually formed by the expansion of a portion of the catheter 2 under heat. The inner diameter of the expansion portion 21 is larger than the inner diameter of the unexpanded portion of the catheter 2, and the inner cavity shape of the formed expansion portion 21 is consistent with the shape of the mold. Preferably, the mold is a conical mold, and the corresponding expansion portion 21 is trumpet-shaped. The inner diameter of the expansion portion 21 gradually decreases from the distal end to the proximal end to the same as the inner diameter of the unexpanded portion of the catheter 2, so as to facilitate the insertion of the proximal end of the balloon.

[0065] “Enlarging one end of the catheter 2 to form the expansion portion 21” includes:

[0066] heating the conical die;

[0067] One end of the conduit 2 is sleeved outside the heated conical mold, and the one end of the conduit 2 is deformed by heat to form the expansion portion 21 .

[0068] It should be noted that it is preferred to use a heater to heat the conical mold, and the temperature of the heater can be set according to the material of the catheter 2 to achieve the purpose of precise temperature control. When the catheter material is pebax 7233, the temperature set by the heater is 110° C. It can be understood that the maximum outer diameter of the conical mold is greater than the inner diameter of the catheter 2, so that when the conical mold is inserted into the catheter 2, one end of the catheter 2 can be deformed.

[0069] In step S2, in order to facilitate the positioning and connection of the catheter 2 and the balloon 1, the step of placing the proximal end of the balloon 1 in the expansion part 21 also includes: a core shaft 3 is passed through the catheter 2 and the balloon 1; the core shaft 3 plays a role in positioning and supporting the catheter 2 and the balloon 1, and the core shaft 3 can support the flow channel in the catheter 2 during the heating process of the catheter 2 and the balloon 1.

[0070] In step S2, “placing the proximal end of the balloon 1 in the expansion portion 21” includes the following steps:

[0071] S21: placing the catheter and the balloon outside the core shaft;

[0072] S22: Move the balloon 1 and / or the catheter 2 along the axial direction of the core shaft 3 so that the proximal end of the balloon 1 extends into the expansion portion 21 of the catheter 2 .

[0073] The core shaft 3 can be used to position the catheter 2 and the balloon 1 after the expansion is completed before they are connected. After the catheter 2 and the balloon 1 are both sleeved on the outside of the core shaft 3, the proximal end of the balloon 1 is extended into the expansion part 21, and the catheter 2 and the balloon 1 overlap at least partially, thereby facilitating the subsequent heating connection.

[0074] In a specific embodiment, the catheter 2 can be firstly sleeved outside the core shaft 3; then the balloon 1 can be sleeved outside the core shaft 3, and the balloon 1 can be moved along the axial direction of the core shaft 3 toward the expansion part 21, so that the proximal end of the balloon 1 is inserted into the expansion part 21 of the catheter 2.

[0075] The balloon 1 is sleeved outside the core shaft 3 and approaches the catheter 2 along the core shaft 3. The expansion portion 21 is conical. The proximal pin 12 of the balloon 1 stops moving after moving to abut against the conical inner wall of the expansion portion 21, thereby completing the positioning of the balloon 1 and the catheter 2 before welding.

[0076] It can be understood that in the above embodiment, the length of the proximal pin 12 extending in the axial direction needs to be greater than the length of the expansion portion 21 extending in the axial direction of the catheter 2 .

[0077] Of course, in other embodiments, the length of the expansion portion 21 extending in the axial direction of the catheter 2 is greater than the length of the proximal pin 12 in the axial direction. When the balloon 1 is sleeved outside the core shaft 3 and approaches the catheter 2 along the core shaft 3, when the end of the proximal pin 12 abuts against the balloon body 11 of the balloon 1, the positioning of the balloon 1 and the catheter 2 before welding is completed.

[0078] In another embodiment, the balloon 1 can be firstly sleeved outside the core shaft 3, and then the catheter 2 can be sleeved outside the core shaft 3, and the catheter 2 can be moved along the circumferential direction of the core shaft 3 to move the expansion portion 21 of the catheter 2 toward the proximal end of the balloon 1.

[0079] Of course, in other embodiments, the catheter 2 is directly moved to a predetermined position after being sleeved on the core shaft 3 , and the balloon 1 can also be directly moved into the expansion portion 21 of the catheter 2 when the balloon 1 is sleeved on the core shaft 3 .

[0080] In addition, the balloon 1 and the catheter 2 may be positioned first, and then the core shaft 3 may be sequentially passed through the balloon 1 and the catheter 2, or the core shaft 3 may be sequentially passed through the catheter 2 and the balloon 1. In other embodiments, the balloon 1 may be sleeved on the core shaft 3 first, and then the catheter 2 may be sleeved on the core shaft 3, and the catheter 2 may be moved to the proximal end of the balloon 1 and sleeved outside the proximal end of the balloon 1.

[0081] Furthermore, in order to facilitate the sleeve arrangement of the catheter 2 and the balloon 1 on the core shaft 3, the present invention further includes: coating the core shaft coating on the core shaft 3 before sleeve arrangement of the catheter 2 and the balloon 1 on the outside of the core shaft 3, wherein the core shaft coating is at least one of a polytetrafluoroethylene coating and a polyparaxylene coating. The provision of the core shaft coating can reduce the friction between the core shaft and the inner wall of the catheter 2, and can make it more convenient to remove the core shaft 3 after welding is completed.

[0082] In the present invention, the material of the core shaft 3 can be stainless steel, and the outer diameter of the core shaft 3 is adapted to the inner diameter of the catheter 2 to ensure that the shape of the catheter 2 does not change during the subsequent welding and heating process, and at the same time, ensure that the channel in the catheter 2 is unobstructed.

[0083] It should be noted that during the welding process, the core shaft 3 also extends into the inner cavity of the balloon 1 to support the proximal end of the balloon 1 .

[0084] In step S3, heating may be performed in one of the following ways.

[0085] In one embodiment, step S3 of "heating the periphery of the expansion portion 21" includes:

[0086] Synchronously rotating the catheter 2 and the balloon 1 along the circumference of the catheter 2;

[0087] Laser welding is performed outside the expansion portion 21, wherein the welding power ranges from 1 to 1.2 W and the welding time is from 5 to 7 s.

[0088] Furthermore, during the laser welding process, the rotation speed of the conduit 2 is 800-1000 rpm, and the welding heat is not less than 6 joules.

[0089] In the present invention, a welding process is used when heating the catheter 2 and the balloon 1. Specifically, resistance welding, ultrasonic welding or radio frequency induction welding can be used. However, the above-mentioned welding methods are not preferred in the balloon catheter welding process due to the large heat-affected zone, unstable welding quality, and the need for a special mandrel. Laser welding is the preferred process in balloon catheter welding due to its advantages of accurate energy input, fast welding speed, high quality, and small welding deformation. Therefore, this embodiment mainly uses laser welding to heat the catheter 2 and the balloon 1. Of course, other heating methods in the prior art can also be used in other embodiments.

[0090] In the present invention, the welding heat is generally controlled at 6-7 joules, so as to ensure that the thick-walled conduit 2 has sufficient heat support before entering the viscous flow state. In this embodiment, since the relatively thick-walled conduit 2 is heated first, sufficient heat is required to conduct the heat to the proximal pin 12 in the conduit 2.

[0091] In order to meet the requirement of heat not less than 6 joules, in a specific embodiment, the laser equipment uses a continuous, far-infrared spectrum laser. This example uses a carbon dioxide continuous laser welder (laser wavelength 10.6μm), and the laser focal length is set to 8-12mm; the welding power of the laser welder ranges from 1-1.2w, and the welding time is 5-7s; during the welding process, the rotation speed of the catheter 2 and the balloon 1 is 800-1000rpm. It should be noted that the welding time here refers to the total time in the welding process.

[0092] Furthermore, “heating the periphery of the expansion portion 21 so that the catheter 2 is connected to the balloon 1 located inside the catheter 2” includes:

[0093] A heat shrink tube 4 is disposed on the outer surface of the catheter 2; wherein the heat shrink tube 4 at least covers the expansion portion 21;

[0094] The outer periphery of the heat shrink tube 4 covering the expansion portion 21 is heated to transform the conduit 2 into a viscous flow state, and the heat shrink tube 4 is heated to shrink to apply pressure outside the expansion portion 21 of the conduit 2 .

[0095] In order to achieve better welding, this embodiment heats the outside of the heat shrink tube 4, and the heat is conducted to the catheter 2 through the heat shrink tube 4. The heat shrink tube 4 provides welding stress during the welding process. The heat shrink tube 4 shrinks after being heated to provide shrinkage force, thereby forming pressure on the catheter 2 on the outside. After being pressed, the catheter 2 is tightly attached to the balloon 1 and finally fixed together. In addition, the setting of the heat shrink tube 4 can locate the welding position relationship between the catheter 2 and the balloon 1 before welding.

[0096] It should be noted that due to the presence of the core shaft 3, during the shrinkage of the heat shrink tube 4, the overlapping part of the catheter 2 and the balloon 1 is actually compressed between the core shaft 3 and the heat shrink tube 4. Such a structural setting can better connect the non-glass catheter 2 with the balloon 1.

[0097] The heat shrink tube 4 generally uses tubes of different diameters to adapt to catheters 2 of different sizes. Other heat shrink materials with lower heat shrinkage temperatures, such as FEP (perfluoroethylene propylene copolymer), may also be used.

[0098] In a specific embodiment, one end of the heat shrink tube 4 can be pressed against the balloon body 11 so that the heat shrink tube 4 completely covers the proximal pin 12. The heat shrink tube 4 is pressed against the balloon body 11 to achieve the coverage of the entire proximal pin 12 by the heat shrink tube 4, so that the catheter 2 can be better connected to the balloon 1 when it shrinks under heat.

[0099] It is understandable that after “heating the periphery of the expansion portion 21 so that the catheter 2 is connected to the balloon 1 located in the catheter 2”, the following steps are also included:

[0100] The heat shrink tube 4 is removed and the mandrel 3 is taken out.

[0101] A specific embodiment is provided below to illustrate the method for manufacturing the balloon dilatation catheter of the present invention in detail.

[0102] The manufacturing method of the balloon dilatation catheter comprises the following steps:

[0103] First, the expansion portion 21 of the conduit 2 is expanded. In this embodiment, a conical mold is used in conjunction with a heater to expand the expansion portion 21 of the conduit 2. The heater heats the conical mold, and the conical mold is then inserted into the end opening of the conduit 2, thereby conducting heat to the conduit 2, so that the conduit 2 can become a viscous flow state;

[0104] Coating a mandrel coating on the mandrel 3, and then inserting the mandrel 3 into the catheter 2;

[0105] The balloon 1 is disposed outside the core shaft 3, and the balloon 1 is moved along the axial direction of the core shaft 3, so that the proximal pin 12 of the balloon 1 moves into the expansion part 21;

[0106] A heat shrink tube 4 is disposed outside the catheter 2, and the heat shrink tube 4 at least covers the expansion portion 21;

[0107] Move the catheter 2, the balloon 1 and the heat shrink tube 4 to the welding workbench, and rotate the catheter 2, the balloon 1 and the heat shrink tube 4 synchronously;

[0108] Start the laser heater outside the welding area, and let the laser act on the outside of the heat shrink tube 4 opposite to the expansion part 21 to weld the heat shrink tube 4, the catheter 2 and the balloon 1;

[0109] After welding, the heat shrink tube 4 is removed and the mandrel 3 is pulled out.

[0110] The invention also discloses a balloon dilatation catheter, which is manufactured by adopting the manufacturing method.

[0111] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings. The above is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown in the drawings. Any changes made according to the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the description and drawings, should be within the protection scope of the present invention.

Claims

1. A method for manufacturing a balloon dilatation catheter, characterized in that: The steps include: enlarging one end of the catheter to form a dilation; placing the proximal end of the balloon within the expansion portion; Heat is applied to the periphery of the expansion portion to connect the expansion portion with the balloon located inside the expansion portion.

2. The method for manufacturing a balloon dilatation catheter according to claim 1, characterized in that: The balloon comprises a balloon body, a proximal pin located at the proximal end of the balloon body, and a distal pin located at the distal end of the balloon body; Before the periphery of the expansion portion is heated, at least a portion of the proximal pins are located in the expansion portion, and the periphery of the expansion portion is heated to connect the expansion portion and the proximal pins.

3. The method for manufacturing a balloon dilatation catheter according to claim 2, characterized in that: The catheter and the balloon are made of the same material and are both formed of a thermoplastic polymer material, wherein the thermoplastic polymer material is a segmented polyetheramide resin.

4. The method for manufacturing a balloon dilatation catheter according to claim 2, characterized in that: “Heating the periphery of the expansion portion to connect the expansion portion to the proximal pin” includes: A heat shrink tube is disposed outside the catheter, and at least a portion of the heat shrink tube covers the expansion portion; The heat shrinkable tube located outside the expansion part is heated to make the conduit become a viscous flow state, and the heat shrinkable tube shrinks under the heat to apply pressure outside the expansion part.

5. The method for manufacturing a balloon dilatation catheter according to claim 2, characterized in that: “Heating the periphery of the expansion portion to connect the expansion portion to the proximal pin” includes: Synchronously rotating the catheter and the balloon along the circumference of the catheter; Laser welding is performed on the periphery of the expansion portion, wherein the welding power ranges from 1 to 1.2 W and the welding time ranges from 5 to 7 s.

6. The method for manufacturing a balloon dilatation catheter according to claim 5, characterized in that: During the laser welding process, the rotation speed of the catheter and the balloon is 800-1000 rpm, and the welding heat is not less than 6 joules.

7. The method for manufacturing a balloon dilatation catheter according to claim 1, characterized in that: "Enlarging one end of the catheter to form a dilated portion" comprises the following steps: heating the conical die; One end of the catheter is sleeved on the heated conical mold, and the one end of the catheter is deformed by heat to form the expansion portion.

8. The method for manufacturing a balloon dilatation catheter according to claim 1, characterized in that: "Placing the proximal end of the balloon in the expansion portion" comprises the following steps: The catheter and the balloon are sheathed outside the core shaft; The balloon and / or the catheter is moved along the axial direction of the core shaft so that the proximal end of the balloon extends into the expansion part.

9. The method for manufacturing a balloon dilatation catheter according to claim 8, characterized in that: Before "arranging the catheter and the balloon outside the core shaft", it also includes: A mandrel coating is coated on the outside of the mandrel, and the mandrel coating is at least one of a polytetrafluoroethylene coating and a polyparaxylene coating.

10. A balloon dilatation catheter, characterized in that: The method is manufactured by the manufacturing method according to any one of claims 1 to 9.

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