JP7145705B2 - Catheter manufacturing method - Google Patents

Description

The present invention relates to a method for manufacturing a catheter.

Conventionally, in the medical field, for example, when treating stenosis or occlusion occurring in a lumen of a living body such as a blood vessel, bile duct, trachea, and esophagus, a stent is used by a catheter inserted into the lumen of the living body. There is known a treatment method of indwelling such as at a site to be treated. Specifically, an operator places a guidewire in advance via an endoscope, and moves a catheter having a stent at its distal end along the guidewire to the vicinity of the site to be treated in the lumen of the living body. Introduce. At this time, when the operator confirms that the stent has reached the vicinity of the site to be treated, the operator can pull the catheter to release the engagement between the stent and the catheter and leave the stent in the body.

In general, catheters are often constructed of a tube whose tip is made of resin and is inserted into the body. A method of embedding a metal imaging tube in a resin tube, which is the distal end of the catheter, is known to facilitate the location of the distal end of the catheter from outside the body.

Patent Document 1 proposes a method for manufacturing a catheter in which a contrast tube is embedded in a resin tube at the distal end of the catheter. The manufacturing method of Patent Document 1 includes a preparatory step of arranging both a cylindrical metal part used as an imaging tube and a metal core inserted into a resin tube in a mold, and and a heating step of heating the mold and the cored bar from the outside of the. In the heating step of the manufacturing method of Patent Literature 1, by heating from the outside of the mold, the metal part for imaging is embedded in the end of the melted resin tube. In the contrast tube manufacturing method of Patent Document 1, the outer diameter of the core bar is set smaller than the inner diameter of the contrast tube.

JP 2010-273876 A

In the manufacturing method of Patent Document 1, when the difference between the outer diameter of the cored bar and the inner diameter of the contrast tube is small, the gap formed between the outer peripheral surface of the cored bar and the inner peripheral surface of the contrast tube (hereinafter referred to as inner ) is also narrow. That is, the inner gap for pouring the melted resin is narrowly formed.

In the manufacturing method of Patent Document 1, a heater is used to heat both the mold and the metal core from the outside of the mold. Due to the heat conduction characteristic, the metal core arranged inside the mold takes longer to be heated to a temperature capable of melting the inner portion of the resin tube, compared to the mold. In this state, the inner peripheral portion of the resin tube facing the outer peripheral portion of the cored bar is insufficiently heated, and the inner peripheral portion of the resin tube may not be melted. As a result, the resin cannot flow well into the narrowly formed inner gap, and in the catheter of Patent Document 1, only a part of the inner portion of the contrast tube may be coated with the resin.

Therefore, when the operator pulls the operation wire to move the catheter to the proximal end side, there is a possibility that the force applied to the catheter may damage the catheter or disconnect the connection between the operation wire and the catheter. be.

In view of the above circumstances, an object of the present invention is to provide a method for manufacturing a catheter that can ensure the strength of the connecting portion between the operation wire and the catheter.

A method for manufacturing a catheter according to an aspect of the present invention is a method for manufacturing a catheter including a tube formed of a resin material, an operation wire, and an anchor member connected to the distal end of the operation wire. A first step of arranging the anchor member at a predetermined position inside a first mold; inserting a bar-shaped core made of a metal material into the first mold; A region sandwiched between the outer peripheral surface of the gold and the inner peripheral surface of the anchor member forms an inner peripheral side gap, and is sandwiched between the outer peripheral surface of the anchor member and the inner peripheral surface of the first mold. a second step of forming an outer peripheral side gap by a region and a region sandwiched between the inner peripheral surface of the first mold and the outer peripheral surface of the core metal; a third step of pressing the tube against the anchor member by inserting the tube into the first mold and applying pressure to the tube in a state in which the tube is inserted through the core metal; A coil arranged outside the first mold is used to subject the cored bar to high-frequency induction heating while maintaining a state of being pressed against the anchor member, so that the heated cored bar pushes the tube from the inside. and a fourth step of heating, wherein in the fourth step, the tube is melted while moving along the direction in which the anchor member is pressed, and the melted resin material of the tube fills the inner gap and the It flows into the outer circumference side gap , and the connecting portion between the operation wire and the anchor member is embedded in the tube.

In the fourth step, the core bar may be moved along the moving direction of the tube at a speed equal to or lower than the moving speed of the tube.
In the first step, the operation wire is inserted and held inside a second mold, and the anchor is moved by moving the first mold with respect to the second mold. A member may be arranged at the predetermined position inside the first mold.
The anchor member and the distal end portion of the operation wire may be joined by welding.
The first mold may be made of a non-metallic material.
In the fourth step, high-frequency induction heating may be applied only to a section of the core bar corresponding to the vicinity of a portion where the tube and the anchor member abut against each other in the entire length of the core bar.
The anchor member may be made of a metal material capable of generating heat by high-frequency induction heating .

According to each of the above aspects of the present invention, it is possible to provide a method for manufacturing a catheter that can secure the strength of the connecting portion between the operation wire and the catheter.

1 is a schematic cross-sectional view showing the configuration of an example of a medical device according to one embodiment of the present invention; FIG. FIG. 2 is a partially enlarged view of part A in FIG. 1; FIG. 3 is a sectional view taken along line II in FIG. 2; FIG. 4 is a schematic diagram showing steps of a method for manufacturing a catheter according to the present embodiment; FIG. 4 is a schematic diagram showing steps of a method for manufacturing a catheter according to the present embodiment; FIG. 4 is a schematic diagram showing steps of a method for manufacturing a catheter according to the present embodiment; FIG. 4 is a schematic diagram showing steps of a method for manufacturing a catheter according to the present embodiment; FIG. 4 is a perspective view showing an example of a mold used in the method of manufacturing a catheter according to the present embodiment; FIG. 3 is a cross-sectional perspective view showing an example of a mold used in the method for manufacturing a catheter according to the present embodiment;

(Configuration of stent delivery system)
The configuration of a catheter according to one embodiment of the present invention will now be described with reference to FIGS. 1 to 3. FIG. FIG. 1 is a schematic cross-sectional view showing the configuration of an example of a medical device according to this embodiment. Specifically, the medical device according to this embodiment is a stent delivery system for placing a stent in a patient's body cavity. FIG. 2 is a partially enlarged view of part A in FIG. 3 is a cross-sectional view taken along line II in FIG. 2. FIG. FIGS. 2 and 3 show the connection structure between the catheter and the operation wire of the stent delivery system according to this embodiment.

A stent delivery system 100 according to this embodiment includes a tubular sheath 10 , a catheter 20 disposed inside the sheath 10 on the distal end side, and an operating section 30 connected to the proximal end side of the sheath 10 . , and a stent 40 connected to the catheter 20 . The sheath 10 has a tubular shape with a longitudinal axis. A lumen through which the operation wire 50 can be inserted is formed inside the sheath 10 .

The catheter 20 is flexible and shaped like a hollow tube. A lumen 21 formed inside the catheter 20 functions, for example, as a flow path through which blood, a drug solution, or the like passes, or a passage through which a guide wire is inserted.

In this embodiment, catheter 20 may be formed of a thermoplastic fluoroelastomer such as, for example, polyvinylidene fluoride elastomer (PVDF).

The operating portion 30 is connected to the proximal end side of the sheath 10 . The operation part 30 is configured to advance and retreat the catheter 20 by operating the operation wire 50 to advance and retreat.
The stent 40 is a member to be placed in a site to be treated, and can be configured with various known structures. For example, the stent 40 may have a mesh tubular shape and be made of a metallic material.

The operation wire 50 is inserted through the sheath 10 so as to be advanced and retracted by advancing and retracting the operating portion 30 . The manipulating wire 50 has a distal end connected to the anchor member 6 . A connecting portion between the distal end portion of the operation wire 50 and the anchor member 6 is embedded in the resin material of the catheter 20 . The operation wire 50 has a base end portion fixed to the operation portion 30 . A configuration of the operation wire 50 is not particularly limited. For example, the operation wire 50 may be composed of a single wire made of various known metals, or may be composed of a twisted wire obtained by twisting a plurality of single wires. In this embodiment, the operator can move the catheter 20 and place the stent 40 connected to the catheter 20 in the body cavity by advancing and retracting the operation wire 50 with the operation portion 30.

(Connection structure between catheter and operation wire)
FIGS. 2 and 3 show the connection structure between the catheter 20 and the operation wire 50 in this embodiment. As shown in FIG. 2, the tip of the operation wire 50 and the anchor member 6 are connected. Also, as shown in FIG. 2 , the connecting portion between the operation wire 50 and the anchor member 6 is embedded in the resin material of the catheter 20 .

In this embodiment, for convenience of explanation, an example in which the anchor member 6 has a pipe shape and is made of a metal material will be described. In this case, the anchor member 6 may have a pipe-shaped inner diameter D1 equal to or greater than the inner diameter D of the catheter 20 . Also, the outer diameter of the anchor member 6 can be appropriately determined according to the dimensions of the catheter 20 . For example, the anchor member 6 may have a maximum outer diameter equal to or less than the outer diameter of the catheter 20 at the connecting portion between the anchor member 6 and the distal end portion of the operation wire 50 .

In this embodiment, the anchor member 6 has, for example, a length L of several millimeters in the longitudinal direction, but is not particularly limited.

In this embodiment, the operating wire 50 is connected to the outer peripheral surface of the anchor member 6 . As a method for connecting the operation wire 50 and the anchor member 6 , various known methods can be appropriately used according to the materials of the operation wire 50 and the anchor member 6 . For example, when the operation wire 50 and the anchor member 6 are made of a metal material, welding the operation wire 50 and the anchor member 6 provides high connection strength. Further, for example, when the anchor member 6 is made of a nonmetallic material such as a resin material, the operation wire 50 and the anchor member 6 may be adhered with an adhesive.
However, a method of welding the operation wire 50 and the anchor member 6 is preferable in order to increase the connection strength at the connection portion between the operation wire 50 and the anchor member 6 .

FIG. 3 is a cross-sectional view taken along the line II in FIG. 2, showing the connection structure between the operation wire 50 and the anchor member 6. As shown in FIG. In the present embodiment, at the connecting portion between the operation wire 50 and the anchor member 6, the distal end portion of the operation wire 50 is formed in a substantially trapezoidal shape. As shown in FIG. 3 , a thin layer of the resin material of the catheter 20 is formed inside the anchor member 6 at the connecting portion between the operation wire 50 and the anchor member 6 . That is, the connecting portion between the operating wire 50 and the anchor member 6 is embedded inside the catheter 20 .

In this embodiment, the operating wire 50 is formed with a circular or substantially circular cross-sectional shape in the range from the operating portion 30 provided on the proximal side of the stent delivery system 100 to the vicinity of the catheter 20 on the distal side. good too. In the range up to the connecting portion between the operation wire 50 and the anchor member 6 in the catheter 20 on the distal end side, the operation wire 50 is formed by deforming the cross-sectional shape from circular or substantially circular to substantially trapezoidal as shown in FIG. may However, in the operation wire 50, the cross-sectional shape of the connecting portion with the anchor member 6 is not limited to the shape shown in FIG. A cross-sectional shape that maximizes the connection area between the operation wire 50 and the anchor member 6 is preferable.

As described above, when the anchor member 6 is not provided, only the distal end portion of the operating wire 50 is embedded in the catheter 20, and the operating wire 50 and the resin material of the catheter 20 are engaged. In this case, when the operator pulls the operation wire 50 toward the proximal end, the force of engagement between the operation wire 50 and the resin material of the catheter 20 may pull the operation wire 50 out of the catheter 20 . In this case, for example, when the operation wire 50 is pulled proximally with a traction force of approximately 20 Newtons, the operation wire 50 may be pulled out of the catheter 20 .

On the other hand, in this embodiment, the connecting portion between the operation wire 50 and the anchor member 6 is embedded inside the catheter 20 . In this case, when the operator pulls the operation wire 50 toward the proximal end, the engagement force between the operation wire 50 and the resin material of the catheter 20, the connection force between the operation wire 50 and the anchor member 6, and the anchor member 6 move toward the catheter. The repulsive force of the resin material acting on the anchor member 6 and the repulsive force of the resin material acting on the anchor member 6 work together to prevent the operation wire 50 alone from being pulled out of the catheter 20 .
Therefore, in this embodiment, when the operation wire 50 is pulled proximally, only the operation wire 50 is pulled out of the catheter 20 unless the connection structure between the operation wire 50 and the anchor member 6 is broken. Prevent.

In the present embodiment, with the catheter 20 and the anchor member 6 formed with the above parameters, even when the operation wire 50 is pulled proximally with a traction force of 50 Newtons or more, the anchor member 6 and the operation wire 50 are not easily separated from each other. It has been confirmed that the connection structure is maintained and the operating wire 50 is not pulled out of the catheter 20 .

(Manufacturing method of catheter)
Next, a method for manufacturing the catheter 20 according to this embodiment will be described with reference to FIGS. 4 to 9. FIG. A method of connecting the anchor member 6 and the operation wire 50 according to the present embodiment and embedding them in the resin material of the catheter 20 in an integrated structure will be mainly described below. Specifically, a method of embedding the connecting portion between the anchor member 6 and the operation wire 50 in the resin material of the catheter 20 by high-frequency induction heating will be described. 4 to 7 are schematic diagrams explaining each step in the manufacturing method of the catheter 20 according to this embodiment. 8 and 9 are schematic diagrams illustrating an example of the configuration of a mold used in the manufacturing method described above. 4 to 7, each step of the manufacturing method according to the present embodiment will be described using schematic cross-sectional views, but the order of each step is not particularly limited.

First, in the preparation process before the high-frequency induction heating process in the method for manufacturing the catheter 20 according to the present embodiment, the process of placing each member in a mold will be described.
The anchor member 6 and the operation wire 50 are connected in advance by welding. In addition, it is a base material for forming a first mold (outer mold) 1, a second mold (inner mold, auxiliary mold) 2, and a catheter 20 used in the manufacturing method according to the present embodiment. A resin tube 4, a metal core 5, and a high-frequency induction heating coil (hereinafter abbreviated as coil) 7 are prepared.

The first mold 1 used in the manufacturing method according to this embodiment is made of a non-metallic material. The first mold 1 may be made of, for example, a heat-resistant resin material such as polyetheretherketone (PEEK). FIG. 9 shows an example of the configuration of the first mold 1 according to this embodiment. As shown in FIG. 9, the first mold 1 is hollow and formed in the shape of a tube. The first mold 1 is internally formed with a first lumen 11 and a second lumen 12 also having a first inner diameter D11. In addition, the first mold 1 has a small diameter portion 14 formed with a second inner diameter D12 smaller than the first inner diameter D11 in a region between the first inner diameter 11 and the second inner diameter 12. have.

The second mold 2 is a mold for arranging the anchor member 6 and the operation wire 50 at predetermined positions and setting the ends of the resin. may be In this embodiment, for example, the second mold 2 may be made of a metal material such as SUS303 that does not generate much heat by high-frequency induction heating.
FIG. 8 shows an example of the configuration of the second mold 2 according to this embodiment. As shown in FIG. 8, the second mold 2 has a tubular main body 2A and projections 2B. As shown in FIG. 8, the main body 2A is partly cut out to be hollow for easy processing. The projecting portion 2B is formed so as to protrude in the longitudinal direction from one end surface of the main body portion 2A. The projecting portion 2B has an outer diameter D21 and is formed in a tubular shape. The projecting portion 2B has a through hole 25 for inserting a metal core 5, which will be described later, and a groove 26 for accommodating the operation wire 50 on the outer peripheral surface.

In this embodiment, for example, the outer diameter D21 of the protrusion 2B of the second mold 2 may be less than or equal to the first inner diameter D11 of the first lumen 11 of the first mold. That is, the first mold 1 and the second mold 2 can be accommodated in the first lumen 11 with the protrusion 2B inserted into the first lumen 11 . Also, the length in the longitudinal direction of the protrusion 2B of the second mold and the depth in the longitudinal direction of the first lumen 11 of the first mold may be substantially the same. That is, in the present embodiment, the protrusion 2B is inserted into the first lumen 11, and the end surface 13 of the first mold 1 and the end surface 27 of the second mold 2 are brought into contact with each other to form the first mold. The mold 1 and the second mold 2 can be engaged with each other.

In the manufacturing method according to this embodiment, first, a holding mechanism (not shown) is used to position and hold the second mold 2 . That is, the second mold 2 can determine the reference position for arranging each member in each step of the manufacturing method according to this embodiment.

At the same time, as shown in FIG. 5, a metal core 5 is inserted into a tube 4 made of a resin material that serves as a base material for forming a catheter 20 (second step). As described above, the tube 4 according to the present embodiment may be made of a thermoplastic fluoroelastomer such as polyvinylidene fluoride elastomer (PVDF). The melting point of the tube 4 according to the present embodiment may be set around 170° C., for example. Further, the cored bar 5 according to this embodiment is made of a metal material capable of generating heat by high-frequency induction heating. For example, the core bar 5 may be made of high speed tool steel (SKH) capable of generating heat by high frequency induction heating. In this embodiment, the outer diameter of the cored bar 5 may be substantially the same as the inner diameter of the tube 4 , that is, the inner diameter D of the catheter 20 .
Then, with the core metal 5 inserted through the tube 4, the core metal 5 is inserted through both the main body 2A of the second mold 2 and the through holes 25 of the protrusions 2B. In this embodiment, the cored bar 5 can be inserted into the second mold 2 and freely moved back and forth.

The anchor member 6 and the operation wire 50 are moved while the core metal 5 is inserted through the through hole 25 of the protrusion 2B of the second mold 2 so that the base end portion of the anchor member 6 is inserted into the second mold 2 . , and the operating wire 50 is accommodated in the groove 26 on the outer peripheral surface of the second mold 2 . After that, the anchor member 6 is moved to a predetermined position. By this step, the positions of the connecting portions of the anchor member 6 and the operation wire 50 are determined with respect to the second mold 2, as shown in FIG.
In this embodiment, the outer diameter of the cored bar 5 is substantially the same as the inner diameter D of the tube 4 , so the outer diameter of the cored bar 5 is smaller than the inner diameter of the anchor member 6 . Therefore, when the cored bar 5 is inserted through the through holes 25 of the body portion 2A and the projection portion 2B of the second mold 2, as shown in FIG. An inner peripheral side gap 61 is formed with a certain distance therebetween.

Next, the connecting portion of the anchor member 6 and the operation wire 50 is held in a state in which the relative position is determined with respect to the second mold 2, and the first mold 1 is moved toward the second mold 2. Moving. In this embodiment, the first mold 1 is placed against the second mold 2 until the end surface 13 of the first mold 1 on the side of the first lumen 11 contacts the end surface 27 of the second mold 2. can move against.
Through this step, as shown in FIG. 6, the connecting portion between the anchor member 6 and the operation wire 50 is arranged at a predetermined position inside the first mold 1 (first step). In this state, the region sandwiched between the outer peripheral surface of the anchor member 6 and the inner peripheral surface of the first lumen 11 of the first mold 1 and the inner peripheral surface of the first mold and the outer peripheral surface of the core metal 5 An outer gap 62 is formed by a region sandwiched between and .

Next, pressure is applied to the tube 4 to move the tube 4 toward the anchor member 6 along the direction in which the metal core 5 extends (third step). In this embodiment, the tube 4 abuts against the anchor member 6 and presses against the anchor member 6 in a state in which the tube 4 is not deformed. In this embodiment, for example, if a force of about 10 Newtons is continuously applied to the tube 4 along the longitudinal axis direction of the tube 4 , the tube 4 can maintain a state of continuing to push the anchor member 6 .

The coil 7 is arranged outside the first mold 1 so as to match the position of the connecting portion between the anchor member 6 and the operation wire 50 inside the first mold 1 .
As described above, the step of arranging each member in the first mold 1 and the second mold 2 as a preparatory step for the method of manufacturing the catheter 20 according to the present embodiment is completed.

In the present embodiment, as an example, it has been described that the steps are executed in the order described above. However, in the present embodiment, as shown in FIG. 6, as a preparation for the high-frequency induction heating step, the connecting portion of the anchor member 6 and the operation wire 50 is arranged at a predetermined position inside the first mold 1. Just decide. In the present embodiment, the order of the above steps is not particularly limited, and may be changed as appropriate.
For example, after determining the relative positions of the anchor member 6 and the operation wire 50 with respect to the second mold 2 and the relative positions of the first mold 1 with respect to the second mold 2, the core metal 5 is placed in the first mold. It is also possible to insert the tube 4 into the metal core 5 into the first mold 1 by inserting it into the mold 1 and the second mold 2 .

The high-frequency induction heating step (fourth step) in this embodiment will be described below.
In high-frequency induction heating, when a metal material is inserted into a coil connected to an AC power supply, the AC current flowing through the coil causes the magnetic field generated in the metal material that is not in contact with the coil to be canceled out. This is a phenomenon in which Joule heat is generated by eddy currents and the electrical resistance of the metal material itself.
In high-frequency induction heating, since the metal material itself generates heat, the heating time can be shortened and the heating efficiency can be improved as compared with the case of heating the metal material by the heat conduction method. Also, by controlling the shape and position of the coil, it is possible to heat only the desired position of the metal material.

In this embodiment, the metal core 5 arranged inside the first mold 1 generates heat by flowing an alternating current through the coil 7 arranged outside the first mold 1 . In this embodiment, the first mold 1 is made of a non-metallic material, and the second mold 2 is made of a metallic or non-metallic material that does not generate heat by high-frequency induction heating. 1 and the second mold 2 do not generate heat.
In this embodiment, the coil 7 is formed in a U-shape and arranged in accordance with the position of the connecting portion of the anchor member 6 and the operation wire 50 . Therefore, the coil 7 can heat the core metal 5 arranged only at the connecting portion between the anchor member 6 and the operation wire 50 and the vicinity thereof. In this embodiment, for example, only the cored bar 5 arranged in a range of about several millimeters on both sides of the entire length of the coil 7 is heated.
In this embodiment, for example, the coil 7 may be used to heat the core metal 5 to about 230°C to 270°C.

In this embodiment, since the core metal 5 is inserted into the tube 4 made of a resin material, the heat generated in the core metal 5 is transferred to the tube 4 by heat conduction, and the resin material of the tube 4 is heated from the inside. and can be melted. In addition, in this embodiment, the efficiency of melting the tube 4 can be improved by applying high-frequency induction heating to the tip portions of the anchor member 6 and the operation wire 50 that are made of a metal material.

In this embodiment, the pressure acting on the tube 4 causes the tube 4 to press against the anchor member 6 as described above. Therefore, when the resin material in the portion of the tube 4 in contact with the anchor member 6 melts, the melted resin material of the tube 4 flows into both the inner gap 61 and the outer gap 62, while the tube 4 is not exposed to pressure. A portion of the melt moves towards the anchor member 6 . In the inner peripheral gap 61 formed between the outer peripheral surface of the core metal 5 and the inner peripheral surface of the anchor member 6, the melted resin material of the tube 4 flows along the core metal 5, so that the anchor member 6, Then, the connecting portion between the anchor member 6 and the operation wire 50 can be wrapped from the inside.

In this embodiment, since the core metal 5 is inserted inside the tube 4, when the tube 4 moves toward the anchor member 6 due to pressure, the action of the frictional force between the core metal 5 and the tube 4 causes The core bar 5 may also move toward the anchor member 6 . When the cored bar 5 moves toward the anchor member 6 , the resin material adhering to the outer peripheral surface of the cored bar 5 can flow into the inner peripheral gap 61 .

Furthermore, a mandrel moving mechanism (not shown) is provided to move the mandrel 5 along the same direction as the direction in which the tube 4 moves toward the anchor member 6 at a speed equal to or lower than the moving speed of the tube 4. good too. With this configuration, the resin material adhering to the outer peripheral surface of the cored bar 5 can be more smoothly poured into the inner peripheral gap 61 .
In this embodiment, the high-frequency induction heating time is not particularly limited, but can be determined based on the outer diameter of the catheter 20 to be manufactured, taking into consideration the desired adhesive strength, cost, etc. comprehensively. For example, when manufacturing a thin catheter 20, the time for high-frequency induction heating may be set within about 20 seconds. Further, for example, when manufacturing a thick catheter 20, the high-frequency induction heating time may be set to about 35 seconds.

In this embodiment, as shown in FIG. 7, when the molten resin material of the tube 4 reaches the end surface of the protrusion 2B of the second mold 2, the coil 7 stops operating. In this state, both the inner gap 61 and the outer gap 62 inside the first mold 1 are filled with the melted resin material of the tube 4 .
This completes the high-frequency induction heating step in the method for manufacturing the catheter 20 according to the present embodiment.

Post-processes in the manufacturing method of the catheter 20 according to the present embodiment will be described below.
In this embodiment, the coil 7 is deactivated before the molten tube 4 is cooled. Therefore, the melted resin material of the tube 4 is solidified, and the catheter 20 is molded. In this embodiment, the method of cooling the tube 4 is not particularly limited, but a method of naturally radiating heat from the tube 4, a method of artificially forcibly cooling the tube 4, or the like can be used.

When the resin material of the tube 4 is completely solidified, the first mold 1 and the second mold 2 are removed, whereby a catheter constructed by embedding the connecting portion of the anchor member 6 and the operation wire 50 in the resin material is manufactured. The molding 20 and the core bar 5 can be taken out together. After that, the cored bar 5 is removed from the catheter 20 .
After that, for example, a step of coating the surface of the catheter 20 with a hydrophilic material and an assembling step of connecting the catheter 20 and other members may be performed.

(action)
According to the method for manufacturing the catheter 20 according to the present embodiment, the resin material of the tube 4 forming the catheter 20 is melted from the inside using high-frequency induction heating, so that the inner space between the metal core 5 and the anchor member 6 is melted. Even if the circumferential gap 61 is small, the molten resin material can be reliably poured. Therefore, the connecting portion between the anchor member 6 and the operation wire 50 can be reliably embedded in the catheter 20 . As a result, desired connection strength can be ensured at the connecting portion between the anchor member 6 of the catheter 20 and the operation wire 50 .

According to the method for manufacturing the catheter 20 according to the present embodiment, by using high-frequency induction heating, only a portion of the core metal 5 corresponding to the connection portion between the anchor member 6 and the operation wire 50 is efficiently heated in a short time. can do. Therefore, the manufacturing time of the catheter 20 can be shortened, and the manufacturing cost can be reduced.

According to the method for manufacturing the catheter 20 according to the present embodiment, by using high-frequency induction heating, the time and output of high-frequency induction heating can be precisely digitally controlled by controlling the alternating current flowing through the coil 7 . Therefore, the catheter 20 manufactured by the manufacturing method according to this embodiment can achieve more stable quality.

Further, according to the catheter 20 manufactured by the manufacturing method according to the present embodiment, since the anchor member 6 and the operation wire 50 are connected with a desired connection strength in the catheter 20, the operation wire 50 is located on the proximal side. When the catheter 20 is pulled, the operation wire 50 alone can be prevented from being pulled out of the catheter 20 and falling off unless the connection structure between the anchor member 6 and the operation wire 50 is destroyed. As a result, the operability and safety of catheter 20 and stent delivery system 100 are improved.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to such embodiments. Configuration additions, omissions, substitutions, and other changes are possible without departing from the scope of the present invention. The present invention can be configured by appropriately combining the components shown in the above-described embodiments.
In one embodiment of the present invention described above, an example in which the anchor member 6 has the shape of a pipe has been described. However, in the present invention, the shape of the anchor member 6 is not limited to this. For example, the anchor member 6 may be formed in a substantially C shape. At this time, the operation wire 50 may be connected to the outer peripheral surface of the substantially C-shaped anchor member 6 . It should be noted that the connecting portion between the substantially C-shaped anchor member 6 and the operation wire 50 can be similarly embedded in the resin material of the tube 4 by the manufacturing method according to the above embodiment of the present invention.
The anchor member 6 may be a tube whose outer peripheral surface is formed of a mesh structure and which is made of a metal material. At this time, the contact area between the molten resin material of the tube 4 and the anchor member 6 increases, so that the connection strength at the connection portion between the anchor member 6 and the operation wire 50 can be further improved.

In one embodiment of the present invention described above, an example in which the anchor member 6 is formed of a metal material has been described. However, in the present invention, the material forming the anchor member 6 is not limited to this. For example, the anchor member 6 may be made of a resin material. At this time, a connection method of bonding the operation wire 50 and the anchor member 6 using an adhesive is also conceivable.
However, from the viewpoint of securing connection strength between the operation wire 50 and the anchor member 6, it is preferable to connect the operation wire 50 and the anchor member 6, which are made of metal material, by welding.

In one embodiment of the present invention described above, an example in which the first mold 1 is made of a heat-resistant resin material such as polyetheretherketone (PEEK) has been described. However, the present invention is not limited to the configuration in which the first mold 1 is made of a resin material. For example, the first mold 1 may be made of a nonmetallic material such as glass or ceramic that has heat resistance and does not generate heat by high-frequency induction heating. However, when the first mold 1 is made of a non-metallic material such as glass or ceramic, heat dissipation is more intense than with a resin such as PEEK, so the temperature for heating the tube 4 is controlled within a certain range. It is difficult. Therefore, in the present embodiment, it is preferable that the first mold 1 is made of a heat-resistant resin material.

The present invention is not limited by the description of the embodiments above, but only by the scope of the appended claims.

1 First mold (outer mold)
2 Second mold (inner mold, auxiliary mold)
4 tube 5 core bar 6 anchor member 7 high frequency induction heating coil (coil)
10 Sheath 20 Catheter 30 Operation Part 40 Stent 50 Operation Wire

Claims (7)

A method for manufacturing a catheter including a tube made of a resin material, an operation wire, and an anchor member connected to the distal end of the operation wire, the method comprising:
a first step of arranging the anchor member at a predetermined position inside a first mold;
A rod-shaped core metal made of a metal material is inserted into the first mold, and an inner peripheral gap is formed by a region sandwiched between the outer peripheral surface of the core metal and the inner peripheral surface of the anchor member. In addition, a region sandwiched between the outer peripheral surface of the anchor member and the inner peripheral surface of the first mold and sandwiched between the inner peripheral surface of the first mold and the outer peripheral surface of the core bar a second step of forming an outer peripheral gap by the region;
The tube is inserted into the first mold until it abuts against the anchor member, and in a state in which the tube is inserted through the core metal, pressure is applied to the tube to move the tube to the anchor member. a third step of pressing against
While maintaining the state in which the tube is pressed against the anchor member, the core metal is heated by high-frequency induction using a coil arranged outside the first mold. a fourth step of heating the tube from the inside;
has
In the fourth step, the tube is melted while moving along the direction in which the anchor member is pressed, and the melted resin material of the tube flows into the inner peripheral side gap and the outer peripheral side gap, and the operation wire and A method for manufacturing a catheter, wherein a connecting portion with the anchor member is embedded in the tube. 2. The method of manufacturing a catheter according to claim 1, wherein in said fourth step, said cored bar is moved along the moving direction of said tube at a speed equal to or lower than the moving speed of said tube. In the first step,
The operation wire is held in a state of being inserted inside the second mold,
3. The method according to claim 1, wherein the anchor member is arranged at the predetermined position inside the first mold by moving the first mold with respect to the second mold. method of manufacturing a catheter. The method of manufacturing a catheter according to any one of claims 1 to 3, wherein the anchor member and the distal end portion of the operation wire are joined by welding. The method of manufacturing a catheter according to any one of claims 1 to 4, wherein the first mold is made of a non-metallic material. 6. The fourth step according to any one of claims 1 to 5, wherein high-frequency induction heating is performed only on a section of the cored bar corresponding to a vicinity of a portion where the tube and the anchor member abut against each other, out of the entire length of the cored bar. 1. A method for manufacturing a catheter according to claim 1. The method of manufacturing a catheter according to any one of claims 1 to 6, wherein the anchor member is made of a metal material capable of generating heat by high-frequency induction heating.

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