JP2020039807A - Method for manufacturing catheter - Google Patents

Abstract

To provide a method for manufacturing a catheter allowing for securement of strength of a connection portion between an operation wire and the catheter.SOLUTION: The method for manufacturing a catheter is a method for manufacturing a catheter comprising a tube (4) formed of resin material, an operation wire, and an anchor member (6) connected to the distal end of the operation wire. The method for manufacturing a catheter has: a first step of arranging an anchor member in a predetermined position inside a first metal mold (1); a second step of inserting a rod-like cored bar (5) formed of metal material into the first metal mold; a third step of inserting the tube into the first metal mold until abutting on the anchor member; and a fourth step of performing high-frequency induction heating on the cored bar using the coil arranged outside the first metal mold while maintaining a state in which the tube is pressed to the anchor member, and thereby heating the tube from the inside by the heated cored bar.SELECTED DRAWING: Figure 7

Description

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

  Conventionally, in the medical field, for example, when treating stenosis or obstruction that has occurred in a lumen in a living body such as blood vessels, bile ducts, trachea, and esophagus, a stent inserted into a lumen in the living body can be used as a stent. There is known a treatment method of placing such an object at a treatment target site. Specifically, the operator pre-places the guide wire via the endoscope, and moves the catheter having the stent disposed at the distal end along the guide wire to the vicinity of the treatment target site in the lumen in the living body. Introduce. At this time, when the operator can confirm that the stent has reached the vicinity of the treatment target site, the operator can release the engagement between the stent and the catheter by pulling the catheter, and place the stent in the body.

  Generally, in many cases, the distal end of a catheter to be inserted into the body is formed of a resin tube. There is known a method of embedding a metal contrast tube in a resin tube, which is a distal end portion of a catheter, in order to easily identify the location of the distal end portion 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 preparation step of disposing both a cylindrical metal part used as a contrast tube and a core metal inserted in a resin tube in a mold, and a mold using a heater. And a heating step of heating the mold and the core from outside. In the heating step of the manufacturing method of Patent Document 1, by heating from the outside of the mold, the metal part for imaging is embedded in the end of the molten resin tube. In the method of manufacturing a contrast tube of Patent Document 1, the outer diameter of the cored bar is set smaller than the inner diameter of the contrast tube.

JP 2010-273876 A

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

  In the manufacturing method of Patent Document 1, both the mold and the core are heated from outside the mold using a heater. Due to the heat conduction characteristics, the core metal disposed inside the mold has a longer time to be heated to a temperature at which the inner portion of the resin tube can be melted, as compared with the mold. In this state, the inner peripheral portion of the resin tube facing the outer peripheral portion of the cored bar may be insufficiently heated, and the inner peripheral portion of the resin tube may not be melted. As a result, it becomes impossible for the resin to flow into the narrow inner circumferential gap, and in the catheter disclosed in Patent Document 1, only a part of the inner portion of the contrast tube may be covered 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 catheter may be damaged or a connection portion between the operation wire and the catheter may be disconnected due to the force applied to the catheter. is there.

  In view of the above circumstances, an object of the present invention is to provide a method for manufacturing a catheter capable of securing the strength of a connection portion between an operation wire and a catheter.

  A method for manufacturing a catheter according to one 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 a distal end portion of the operation wire. A first step of arranging the anchor member at a predetermined position inside the first mold; and inserting a rod-shaped core made of a metal material into the first mold; A second step of forming a gap between the outer peripheral surface of gold and the inner surface of the anchor member, and inserting the tube into the first mold until the tube comes into contact with the anchor member; A third step of pressing the tube against the anchor member by applying pressure to the tube in a state where the tube is inserted into the gold, while maintaining the state where the tube is pressed against the anchor member. And a fourth step of heating the tube from the inside with the heated core by heating the core with high frequency induction using a coil disposed outside the first mold, In the fourth step, the tube is melted while moving along the direction of pressing the anchor member, the melted resin material of the tube flows into the gap, and the connecting portion between the operation wire and the anchor member is It is embedded in the tube.

In the fourth step, the cored 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 held in a state inserted into 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 of the operation wire may be joined by welding.
The first mold may be formed of a non-metallic material.
In the fourth step, only high frequency induction heating may be performed on a section of the entire length of the core bar corresponding to the vicinity of a portion where the tube and the anchor member abut.
The anchor member may be formed 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 of manufacturing a catheter that can secure the strength of a connection portion between the operation wire and the catheter.

It is a typical sectional view showing composition of an example of a medical device concerning one embodiment of the present invention. It is the elements on larger scale of the A section in FIG. It is II sectional drawing in FIG. It is a schematic diagram which shows the process of the manufacturing method of the catheter which concerns on this embodiment. It is a schematic diagram which shows the process of the manufacturing method of the catheter which concerns on this embodiment. It is a schematic diagram which shows the process of the manufacturing method of the catheter which concerns on this embodiment. It is a schematic diagram which shows the process of the manufacturing method of the catheter which concerns on this embodiment. It is a perspective view showing an example of a metallic mold used in a manufacturing method of a catheter concerning this embodiment. It is a sectional perspective view showing an example of a metallic mold used in a manufacturing method of a catheter concerning this embodiment.

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

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

  The catheter 20 has flexibility and is formed in a hollow tube shape. The lumen 21 formed inside the catheter 20 functions as, for example, a flow path through which blood or a drug solution passes, or a path through which a guide wire is inserted.

  In the present embodiment, the catheter 20 may be formed of, for example, a fluoroelastomer having thermoplasticity such as polyvinylidene fluoride elastomer (PVDF).

The operation unit 30 is connected to the proximal end side of the sheath 10. The operation unit 30 is configured to move the catheter 20 forward and backward by operating the operation wire 50 forward and backward.
The stent 40 is a member to be placed at a treatment target site, and can be configured with various known structures. For example, the stent 40 may have a mesh cylindrical shape, and may be formed of a metal material.

  The operation wire 50 is inserted into the sheath 10 so as to be able to advance and retreat by an advance and retreat operation of the operation unit 30. The distal end of the operation wire 50 is connected to the anchor member 6. The connection between the distal end of the operation wire 50 and the anchor member 6 is embedded in the resin material of the catheter 20. The proximal end of the operation wire 50 is fixed to the operation unit 30. The configuration of the operation wire 50 is not particularly limited. For example, the operation wire 50 may be formed of various known single wires made of metal, or may be formed of a stranded wire obtained by twisting a plurality of single wires. In the present embodiment, the operator can move the catheter 20 by advancing and retracting the operation wire 50 with the operation unit 30, and can place the stent 40 connected to the catheter 20 in a body cavity.

(Connection structure between catheter and operation wire)
2 and 3 show a connection structure between the catheter 20 and the operation wire 50 in the present embodiment. As shown in FIG. 2, the distal end of the operation wire 50 and the anchor member 6 are connected. As shown in FIG. 2, the connection 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 formed of a metal material will be described. In this case, the anchor member 6 only needs to have a pipe-shaped inner diameter D1 equal to or larger than the inner diameter D of the catheter 20. 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 only needs to have a maximum outer diameter of a connection portion between the anchor member 6 and the distal end of the operation wire 50 that is equal to or less than the outer diameter of the catheter 20.

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

In the present embodiment, the operation wire 50 is connected to the outer peripheral surface of the anchor member 6. As a method of 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 formed of a metal material, a high connection strength can be obtained by welding the operation wire 50 and the anchor member 6. Further, for example, when the anchor member 6 is formed of a non-metallic material, for example, a resin material, the operation wire 50 and the anchor member 6 may be bonded with an adhesive.
However, in order to increase the connection strength at the connection portion between the operation wire 50 and the anchor member 6, a method of welding the operation wire 50 and the anchor member 6 is preferable.

  FIG. 3 is a sectional view taken along the line II in FIG. 2, and shows a connection structure between the operation wire 50 and the anchor member 6. In the present embodiment, at the connection portion between the operation wire 50 and the anchor member 6, the distal end 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 connection portion between the operation wire 50 and the anchor member 6. That is, the connection portion between the operation wire 50 and the anchor member 6 is embedded in the catheter 20.

  In the present embodiment, in a range from the operation section 30 provided on the proximal end side of the stent delivery system 100 to the vicinity of the catheter 20 on the distal end side, the operation wire 50 has a circular or substantially circular cross section. Is also good. Then, in a range up to a connection 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 a circular or substantially circular shape to a substantially trapezoidal shape shown in FIG. You may. However, in the operation wire 50, the cross-sectional shape at the connection portion with the anchor member 6 is not limited to the shape shown in FIG. A cross-sectional shape in which the connection area between the operation wire 50 and the anchor member 6 is as large as possible is preferable.

  As described above, when the anchor member 6 is not provided, only the distal end portion of the operation wire 50 is embedded in the catheter 20, and the operation wire 50 and the resin material of the catheter 20 are engaged. In this case, when the operator pulls the operation wire 50 to the proximal end side, the operation wire 50 may be pulled out of the catheter 20 due to the engagement force between the operation wire 50 and the resin material of the catheter 20. In this case, for example, when the operation wire 50 is pulled toward the proximal end with a pulling force of about 20 Newton, the operation wire 50 may be pulled out of the catheter 20 in some cases.

On the other hand, in the present embodiment, the connection between the operation wire 50 and the anchor member 6 is embedded in the catheter 20. In this case, when the operator pulls the operation wire 50 to the proximal end side, 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 By biting into the resin material 20, the repulsive force of the resin material acting on the anchor member 6 acts comprehensively, thereby preventing only the operation wire 50 from being pulled out from the catheter 20.
For this reason, in the present embodiment, when the operation wire 50 is pulled toward the proximal end side, only the operation wire 50 is pulled out from the catheter 20 unless the connection structure between the operation wire 50 and the anchor member 6 is broken. Can be prevented.

  In the present embodiment, according to the catheter 20 and the anchor member 6 formed with the above-described parameters, even when the operation wire 50 is pulled to the proximal end side with a traction force of 50 Newton or more, the anchor member 6 and the operation wire 50 It has been confirmed that the connection structure is maintained and the operation wire 50 is not pulled out of the catheter 20.

(Method of manufacturing catheter)
Next, a method for manufacturing the catheter 20 according to the present embodiment will be described with reference to FIGS. Hereinafter, a method for embedding the anchor member 6 and the operation wire 50 according to the present embodiment in the resin material of the catheter 20 in an integrated structure will be mainly described. Specifically, a method of embedding the connection 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 views illustrating each step in the method for manufacturing the catheter 20 according to the present embodiment. 8 and 9 are schematic diagrams illustrating an example of a configuration of a mold used in the above-described manufacturing method. 4 to 7, each step of the manufacturing method according to the present embodiment will be described with reference to schematic cross-sectional views, but the order of each step is not particularly limited.

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

  The first mold 1 used in the manufacturing method according to the present embodiment is formed of a non-metallic material. The first mold 1 may be formed of a heat-resistant resin material such as polyetheretherketone (PEEK), for example. FIG. 9 shows an example of the configuration of the first mold 1 according to the present embodiment. As shown in FIG. 9, the first mold 1 is hollow and has a tube shape. The first mold 1 has a first lumen 11 and a second lumen 12 formed therein with the first inner diameter D11. Further, 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 lumen 11 and the second lumen 12. Have.

The second mold 2 is a mold that arranges the anchor member 6 and the operation wire 50 at predetermined positions and sets an end of the resin, and may be formed of a metal material or formed of a non-metal material. May be done. In the present embodiment, for example, the second mold 2 may be formed 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 the present embodiment. As shown in FIG. 8, the second mold 2 has a cylindrical main body 2A and a protrusion 2B. As shown in FIG. 8, the main body 2 </ b> A is partly cut out and hollow to facilitate processing. The protrusion 2B is formed to protrude in the longitudinal direction from one end face of the main body 2A. The protrusion 2B has an outer diameter D21 and is formed in a tubular shape. In the protruding portion 2B, a through hole 25 for inserting the core metal 5 described later and a groove 26 for accommodating the operation wire 50 are formed on the outer peripheral surface.

  In the present embodiment, for example, the outer diameter D21 of the protrusion 2B of the second mold 2 may be equal to or less than the first inner diameter D11 of the first cavity 11 of the first mold. That is, the protrusions 2B of the first mold 1 and the second mold 2 can be inserted into the first lumen 11 and housed in the first lumen 11. Further, the length of the projection 2B of the second mold in the longitudinal direction may be substantially equal to the depth of the first cavity 11 of the first mold in the longitudinal direction. That is, in the present embodiment, the protrusion 2 </ b> B is inserted into the first lumen 11, and the end face 13 of the first mold 1 and the end face 27 of the second mold 2 come into contact with each other, whereby the first The mold 1 and the second mold 2 can engage with each other.

  In the manufacturing method according to the present embodiment, first, the position of the second mold 2 is determined and held using a holding mechanism (not shown). That is, the second mold 2 can determine the reference position where each member is arranged in each step of the manufacturing method according to the present embodiment.

At the same time, as shown in FIG. 5, the core metal 5 is inserted into the tube 4 formed of a resin material serving as a base material for forming the catheter 20 (second step). As described above, the tube 4 according to the present embodiment may be formed of, for example, a fluoroelastomer having thermoplasticity such as polyvinylidene fluoride elastomer (PVDF). For example, the melting point of the tube 4 according to the present embodiment may be set at around 170 ° C. Further, the metal core 5 according to the present embodiment is formed of a metal material that can generate heat by high-frequency induction heating. For example, the core metal 5 may be formed of high-speed tool steel (SKH) that can generate heat by high-frequency induction heating. In the present embodiment, the outer diameter of the cored bar 5 may be substantially equal to the inner diameter of the tube 4, that is, the inner diameter D of the catheter 20.
Then, with the core 5 inserted into the tube 4, the core 5 is inserted into both the main body 2 </ b> A of the second mold 2 and the through hole 25 of the projection 2 </ b> B. In the present embodiment, the core metal 5 can be inserted into the second mold 2 and freely move forward and backward.

The anchor member 6 and the operation wire 50 are moved in a state where the core metal 5 is inserted into the through hole 25 of the projection 2B of the second mold 2, and the base end of the anchor member 6 is moved to the second mold 2. And the operation wire 50 is housed in the groove 26 on the outer peripheral surface of the second mold 2. Thereafter, the anchor member 6 is moved to a predetermined position. In this step, as shown in FIG. 6, the positions of the connecting portions of the anchor member 6 and the operation wire 50 with respect to the second mold 2 are determined.
In the present embodiment, since the outer diameter of the core 5 is substantially equal to the inner diameter D of the tube 4, the outer diameter of the core 5 is smaller than the inner diameter of the anchor member 6. For this reason, when the core 5 is inserted into the through-hole 25 of the main body 2A and the projection 2B of the second mold 2, as shown in FIG. 6, the outer peripheral surface of the core 5 and the inner peripheral surface of the anchor member 6 are formed. , An inner circumferential gap 61 is formed at a certain distance.

Next, while maintaining the state where the connection between the anchor member 6 and the operation wire 50 is determined relative to the second mold 2, the first mold 1 is moved toward the second mold 2. Moving. In the present embodiment, the first mold 1 is connected to the second mold 2 until the end face 13 of the first mold 1 on the side of the first cavity 11 contacts the end face 27 of the second mold 2. You can move around.
By this step, as shown in FIG. 6, the connection 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, an outer circumferential gap 62 is formed at a fixed distance between the outer circumferential surface of the anchor member 6 and the inner circumferential surface of the first cavity 11 of the first mold 1.

  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 the present embodiment, the tube 4 comes into contact with the anchor member 6 and is pressed against the anchor member 6 in a state where the tube 4 is not deformed. In the present embodiment, for example, when a force of about 10 Newton is continuously applied to the tube 4 along the longitudinal axis direction of the tube 4, the state in which the tube 4 is continuously pressed against the anchor member 6 can be maintained.

The coil 7 is arranged outside the first mold 1 in accordance with the position of the connection 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 is completed as a preparation step of the method for manufacturing the catheter 20 according to the present embodiment.

In the present embodiment, as an example, it has been described that the respective 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, a state in which the connection portion between the anchor member 6 and the operation wire 50 is arranged at a predetermined position inside the first mold 1. You just have to decide. In the present embodiment, the order of the above steps is not particularly limited, and may be appropriately changed.
For example, after determining the relative position of the anchor member 6 and the operation wire 50 with respect to the second mold 2 and the relative position of the first mold 1 with respect to the second mold 2, the core metal 5 is moved to the first mold. The tube 4 can also be inserted into the first metal mold 1 by inserting the tube 4 into the metal mold 1 and the second metal mold 2.

Hereinafter, the high-frequency induction heating step (fourth step) in the present embodiment will be described.
Generally, when a metal material or the like is inserted into a coil connected to an AC power supply, high-frequency induction heating is generated in a direction to cancel a magnetic field generated in a metal material that is not in contact with the coil due to an alternating current flowing through the coil. This is a phenomenon in which Joule heat is generated by eddy current and electric resistance of the metal material itself.
In the 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 where the metal material is heated by a heat conduction method. Further, it is possible to heat only a desired position of the metal material by controlling the shape and the arrangement position of the coil.

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

  In the present embodiment, since the metal core 5 is inserted into the tube 4 made of a resin material, the heat generated in the metal core 5 is transmitted 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 this embodiment, the efficiency of melting the tube 4 can be improved by high-frequency induction heating of the anchor member 6 and the distal end of the operation wire 50 formed of a metal material.

  In the present embodiment, as described above, the tube 4 is pressed against the anchor member 6 by the pressure acting on the tube 4. For this reason, when the resin material in the portion where the tube 4 comes into contact with the anchor member 6 is melted, the molten resin material of the tube 4 flows into both the inner circumferential gap 61 and the outer circumferential gap 62, while the pressure of the tube 4 is reduced by the pressure. The melted part moves toward the anchor member 6. In the inner circumferential gap 61 formed between the outer peripheral surface of the cored bar 5 and the inner peripheral surface of the anchor member 6, the molten resin material of the tube 4 flows along the cored bar 5. And the connection part of the anchor member 6 and the operation wire 50 can be wrapped from the inside.

  In the present embodiment, since the metal core 5 is inserted into the inside of the tube 4, when the tube 4 moves toward the anchor member 6 by the pressure, the frictional force between the metal core 5 and the tube 4 acts. The core metal 5 may also move toward the anchor member 6. When the metal core 5 moves toward the anchor member 6, the resin material attached to the outer peripheral surface of the metal core 5 can flow into the inner peripheral gap 61.

Further, a core metal moving mechanism (not shown) is provided to move the metal core 5 at a speed equal to or lower than the moving speed of the tube 4 in the same direction as the direction in which the tube 4 moves toward the anchor member 6. Is also good. With this configuration, the resin material attached to the outer peripheral surface of the cored bar 5 can be more smoothly poured into the inner peripheral gap 61.
In the present embodiment, the time for high-frequency induction heating 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, and the like. For example, when manufacturing the thin catheter 20, the time for high-frequency induction heating may be set to about 20 seconds or less. Further, for example, when manufacturing the thick catheter 20, the time for high-frequency induction heating may be set to about 35 seconds.

In the present embodiment, as shown in FIG. 7, when the molten resin material of the tube 4 reaches the end surface of the projection 2B of the second mold 2, the operation of the coil 7 is stopped. In this state, inside the first mold 1, both the inner circumferential gap 61 and the better outer circumferential gap 62 are filled with the molten resin material of the tube 4.
Thus, the high-frequency induction heating step in the method for manufacturing the catheter 20 according to the present embodiment is completed.

Hereinafter, a post-process in the method for manufacturing the catheter 20 according to the present embodiment will be described.
In the present embodiment, the molten tube 4 is cooled after the operation of the coil 7 is stopped. Therefore, the molten resin material of the tube 4 is solidified, and the catheter 20 is formed. In the present embodiment, the method of cooling the tube 4 is not particularly limited, and a method of naturally radiating the heat of the tube 4 and a method of artificially forcibly cooling the tube 4 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, so that the connection portion between the anchor member 6 and the operation wire 50 is embedded in the resin material. The molded product 20 and the core metal 5 can be taken out integrally. Thereafter, the core 5 is removed from the catheter 20.
Thereafter, for example, a step of coating the surface of the catheter 20 with a hydrophilic material and an assembly 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 by using high-frequency induction heating, so that the inner space between the cored bar 5 and the anchor member 6 is increased. Even when the circumferential gap 61 is small, the molten resin material can be reliably poured. Therefore, the connection between the anchor member 6 and the operation wire 50 can be reliably embedded in the catheter 20. As a result, a desired connection strength at the connection portion between the anchor member 6 of the catheter 20 and the operation wire 50 can be secured.

  According to the method for manufacturing the catheter 20 according to the present embodiment, by using high-frequency induction heating, only a part of the core metal 5 corresponding to the connection 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 reduced, and the manufacturing cost can be reduced.

  According to the method of manufacturing the catheter 20 according to the present embodiment, by using the high-frequency induction heating and controlling the alternating current flowing through the coil 7, the time and output of the high-frequency induction heating can be precisely digitally controlled. Therefore, the catheter 20 manufactured by the manufacturing method according to the present embodiment can realize 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 connected to the proximal end side. If the connection wire between the anchor member 6 and the operation wire 50 is broken, it is possible to prevent only the operation wire 50 from being pulled out of the catheter 20 and falling off. As a result, the operability and safety of the catheter 20 and the stent delivery system 100 are improved.

The preferred embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment. Additions, omissions, substitutions, and other modifications of the configuration can be made without departing from the spirit 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 a pipe shape 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. The connection between the substantially C-shaped anchor member 6 and the operation wire 50 can be similarly buried in the resin material of the tube 4 by the manufacturing method according to the above-described embodiment of the present invention.
The anchor member 6 may be a tube whose outer peripheral surface is formed in a mesh structure and formed of a metal material. At this time, the contact area between the resin material of the melted tube 4 and the anchor member 6 is increased, so that the connection strength at the connection portion between the anchor member 6 and the operation wire 50 can be further improved.

In the above-described embodiment of the present invention, 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 formed of a resin material. At this time, a connection method for bonding the operation wire 50 and the anchor member 6 using an adhesive is also conceivable.
However, from the viewpoint of securing the connection strength between the operation wire 50 and the anchor member 6, a method of connecting the operation wire 50 and the anchor member 6 each formed of a metal material by welding is preferable.

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

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

1 first mold (outer mold)
2 Second mold (inner mold, auxiliary mold)
4 Tube 5 Core 6 Anchor 7 High frequency induction heating coil (coil)
Reference Signs List 10 sheath 20 catheter 30 operation part 40 stent 50 operation wire

Claims (7)

A method for manufacturing a catheter including a tube formed of a resin material, an operation wire, and an anchor member connected to a distal end portion of the operation wire,
A first step of disposing the anchor member at a predetermined position inside a first mold;
A second step of inserting a rod-shaped core metal formed of a metal material into the inside of the first mold, and forming a gap between an outer peripheral surface of the core metal and an inner surface of the anchor member;
The tube is inserted into the first mold until it comes into contact with the anchor member, and pressure is applied to the tube in a state where the tube is inserted through the cored bar, thereby connecting 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 bar is subjected to high-frequency induction heating using a coil arranged outside the first mold, so that the core bar that has generated heat is used. 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, the melted resin material of the tube flows into the gap, and a connection between the operation wire and the anchor member is formed. A method for producing a catheter embedded in the tube.   The method for manufacturing a catheter according to claim 1, wherein, in the fourth step, the core metal is 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 held in a state of being inserted inside the second mold,
The said 1st metal mold | die is moved with respect to the said 2nd metal mold | die, The said anchor member is arrange | positioned in the said predetermined position inside the said 1st metal mold | die. Method for manufacturing a catheter.   The method for 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 for manufacturing a catheter according to any one of claims 1 to 4, wherein the first mold is formed of a nonmetallic material.   6. The high-frequency induction heating of only the core metal in a section corresponding to the vicinity of a portion where the tube and the anchor member come into contact with each other in the entire length of the core metal in the fourth step. 2. The method for producing a catheter according to item 1.   The method for manufacturing a catheter according to any one of claims 1 to 6, wherein the anchor member is formed of a metal material capable of generating heat by high-frequency induction heating.

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