catheter

Abstract

This catheter 10 is provided with a catheter tube 11 and a connector 12 connected to the base end part 11a of the catheter tube 11. The connector 12 has a body part 17 in which is formed an insertion hole 16 for inserting the base end part 11a of the catheter tube 11, and a cylindrical extension part 18 extending towards the distal end side from the body part 17. The extension part 18 is set away from a tube draw-out portion 22 of the catheter tube 11 that is drawn out towards the distal end side from the insertion hole 16, and surrounds a part of the tube draw-out portion 22.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Application No. 2021-186242 filed on November 16, 2021, the contents of which are incorporated herein by reference. [Technical field]

[0002] The present disclosure relates to catheters. [Background technology]

[0003] Generally, a catheter comprises a catheter tube that is introduced into the body, and a connector connected to the base end of the catheter tube (see, for example, Patent Document 1). The connector has an insertion hole into which the base end of the catheter tube is inserted, and the base end inserted into the insertion hole is joined to the connector by welding or adhesive. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-090717 A Summary of the Invention [Problem to be solved by the invention]

[0005] When a catheter is introduced into a body, the tube lead-out portion of the catheter tube that is led out from the insertion hole to the distal end side may be bent relative to the joint portion joined to the connector. In this case, if the amount of bending of the tube lead-out portion is large, the catheter tube may bend at the boundary between the joint portion with the connector and the tube lead-out portion, causing a kink. In particular, since the catheter tube has a large difference in hardness between the joint portion and the tube lead-out portion, it is considered that kinking is likely to occur at the boundary portion.

[0006] The present disclosure has been made in consideration of the above circumstances, and has as its main object to provide a catheter capable of suppressing the occurrence of kinking. [Means for solving the problem]

[0007] In order to solve the above problems, a catheter disclosed in a first disclosure includes a catheter tube and a connector connected to a base end of the catheter tube, the connector having an insertion hole into which the base end of the catheter tube is inserted and joined to the base end inserted into the insertion hole, and the connector is provided on the distal side of the insertion hole and has a tubular or annular surrounding portion that surrounds a part of a tube lead-out portion of the catheter tube that is led out from the insertion hole to the distal side, at a position spaced from the tube lead-out portion.

[0008] According to the first disclosure, the base end of the catheter tube is joined to the connector in a state where it is inserted into the insertion hole of the connector. A part of the tube lead-out portion of the catheter tube led out from the insertion hole to the tip side is surrounded by the surrounding portion of the connector. In this case, if the tube lead-out portion is bent when the catheter is introduced into the body, the amount of bending is limited by the surrounding portion. This makes it possible to suppress the occurrence of kinking in the catheter tube at the boundary between the joint portion with the connector and the tube lead-out portion.

[0009] The catheter of the second disclosure is the catheter of the first disclosure, wherein the connector has a main body portion in which the insertion hole is formed and a tubular extension portion extending from the main body portion toward the tip side, and the extension portion forms the surrounding portion.

[0010] When the bending amount of the tube lead-out portion of the catheter tube is limited by the surrounding portion, a load acts radially outward from the tube lead-out portion on the surrounding portion. In this regard, in the second disclosure, the connector has a main body portion in which an insertion hole is formed, and a tubular extending portion extending from the main body portion to the tip side, and the extending portion serves as a surrounding portion that surrounds a part of the tube lead-out portion. In this case, the above-mentioned load acting on the extending portion (enclosing portion) can be received in a stable state.

[0011] The catheter of the third disclosure is the catheter of the second disclosure, wherein the inner surface of the extension portion includes a tapered surface that is enlarged in diameter toward the tip side.

[0012] According to the third disclosure, when the tube leading-out portion of the catheter tube is bent, the tube leading-out portion can be brought into contact with the tapered surface of the extension portion, thereby making it possible to prevent stress concentration from occurring in the tube leading-out portion, and as a result, to prevent kinking caused by stress concentration.

[0013] The catheter of a fourth disclosure is the catheter of the third disclosure, wherein the tapered surface is continuous with the circumferential surface of the insertion hole.

[0014] According to the fourth disclosure, since the tapered surface and the peripheral surface of the insertion hole are continuous, there is no step at the boundary between the tapered surface and the peripheral surface of the insertion hole. In this case, it is possible to more reliably prevent the catheter tube from bending at the boundary between the joint portion inserted into the insertion hole and joined to the connector, and the tube lead-out portion led out from the insertion hole. Therefore, it is possible to more reliably prevent kinking at the boundary.

[0015] The catheter of the fifth disclosure is the catheter of the second disclosure, wherein the inner diameter of the extension portion at its base end is larger than the diameter of the insertion hole, and the inner diameter of the extension portion is either the same from the base end to the tip end of the extension portion or is larger from the base end to the tip end.

[0016] When a force toward the base end acts on the catheter tube when the catheter is introduced into the body, it is assumed that the tube lead-out portion of the catheter tube will bend in a convex (bulge) shape in a direction perpendicular to the axial direction near its base end. In this regard, according to the fifth disclosure, the extension portion is configured as described above, so that a wide inner space of the extension portion can be secured from the base end to the tip end. This allows the base end portion of the tube lead-out portion to bend smoothly in the inner space of the extension portion, and as a result, it is possible to suppress the occurrence of kinking near the base end of the tube lead-out portion.

[0017] The catheter of a sixth disclosure is any one of the first to fifth disclosures, wherein the inner surface of the tip of the surrounding portion is a curved portion formed so that the inner diameter increases toward the tip.

[0018] When the bending amount of the tube lead-out portion is limited by the extension portion, if a bending force is further applied to the tube lead-out portion, the tube lead-out portion may bend at the tip of the extension portion. In this regard, according to the sixth disclosure, since the inner surface of the tip of the extension portion is a curved portion, the tube lead-out portion is bent along the curved portion at the tip of the extension portion. Therefore, it is possible to prevent the tube lead-out portion from bending at the tip of the extension portion. This makes it possible to prevent the occurrence of kinking due to such bending.

[0019] The catheter of the seventh disclosure is any of the first to sixth disclosures, wherein the base end of the catheter tube inserted into the insertion hole has a non-jointed portion that is not joined to the connector and is distal to the joint portion joined to the connector.

[0020] According to the seventh disclosure, the proximal end of the catheter tube inserted into the insertion hole is not joined to the distal end of the catheter tube relative to the joint with the connector. This reduces the hardness difference (hardness change) between the joint with the connector and the tube lead-out portion of the catheter tube led out from the insertion hole. This makes it possible to suppress the occurrence of kinking due to the hardness difference.

[0021] The catheter of an eighth disclosure is any one of the first to seventh disclosures, wherein the connector has a main body portion in which the insertion hole is formed and the surrounding portion formed integrally therewith.

[0022] As described above, when the bending amount of the tube lead-out portion is limited by the surrounding portion, a load acts from the tube lead-out portion to the surrounding portion in the radially outward direction. In this regard, according to the eighth disclosure, since the main body portion having the insertion hole and the surrounding portion are integrally formed in the connector, it is possible to prevent the surrounding portion from coming off the main body portion due to the load.

[0023] A ninth disclosure is a catheter according to any one of the first to eighth disclosures, wherein the connector is formed to be optically transparent, the catheter tube is formed to be optically absorbing, and the connector is joined to a base end of the catheter tube by welding.

[0024] According to the ninth disclosure, the connector is optically transparent, and the catheter tube is optically absorbing. In this case, the connector and the catheter tube can be laser welded at their interface by irradiating the interface between them with laser light via the connector. This allows the thickness of the welded portion between the connector and the catheter tube to be relatively thin, and as a result, the difference in hardness between the joint portion with the connector (welded portion) and the tube lead-out portion of the catheter tube can be reduced. Therefore, the occurrence of kinks due to the difference in hardness can be further suppressed. [Brief description of the drawings]

[0025] The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Figure 1] FIG. 2 is a cross-sectional view showing the periphery of a joint between a catheter tube and a connector in the catheter in the first embodiment. [Diagram 2] 13 is a cross-sectional view for explaining the function of the extension portion. FIG. [Diagram 3] FIG. 11 is a cross-sectional view showing the periphery of a joint between a catheter tube and a connector in a catheter according to a second embodiment. [Figure 4] 13 is a cross-sectional view for explaining the function of the extension portion. FIG. [Diagram 5] FIG. 11 is a cross-sectional view showing the periphery of an extension portion of a connector according to another embodiment. [Figure 6] FIG. 11 is a cross-sectional view showing the periphery of an extension portion of a connector according to another embodiment. [Figure 7] FIG. 11 is a cross-sectional view showing the periphery of an extension portion of a connector according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] [First embodiment] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present disclosure will now be described with reference to the drawings. Fig. 1 is a cross-sectional view showing the junction between a catheter tube 11 and a connector 12 in a catheter 10 and the surrounding area.

[0027] As shown in Fig. 1, a catheter 10 includes a catheter tube 11 and a connector 12 connected to the base end (proximal end) of the catheter tube 11. The catheter tube 11 is formed in a cylindrical shape and has an inner cavity 13 extending throughout the entire axial direction. The catheter tube 11 is made of a soft resin having flexibility, for example, polyamide. The catheter tube 11 is colored black and has light absorbing properties.

[0028] The catheter 10 is, for example, a contrast catheter, but may be another catheter such as a balloon catheter or a suction catheter.

[0029] The connector 12 is made of a hard resin, for example, polyamide. The connector 12 is formed in a cylindrical shape as a whole, and has a hole 14 that penetrates the connector 12 in the axial direction. The connector 12 is formed to be transparent or semi-transparent, and has optical transparency. The connector 12 is also called a hub. The connector 12 may be made of a hard resin other than polyamide, such as polyacetal, polycarbonate, or ABS.

[0030] The connector 12 has a main body 17 having an insertion hole 16 into which the base end 11a of the catheter tube 11 is inserted, and an extension 18 extending from the main body 17 to the tip side. The insertion hole 16 constitutes a part of the hole 14, and has a hole diameter that is approximately the same as the outer diameter of the catheter tube 11. Moreover, the insertion hole 16 has a constant hole diameter over the entire area in the axial direction.

[0031] The base end 11a of the catheter tube 11 inserted into the insertion hole 16 is joined to the main body 17 by welding. In this embodiment, the base end 11a of the catheter tube 11 is joined to the main body 17 by laser welding. The main body 17 and the base end 11a of the catheter tube 11 are laser welded to each other at their interface. Here, to explain laser welding, a laser beam is irradiated to the interface between the main body 17 and the base end 11a of the catheter tube 11 via the connector 12. Then, the irradiated laser beam generates heat at the interface, and the generated heat melts the main body 17 and the base end 11a, so that the two 11a and 17 are welded to each other.

[0032] The main body 17 extends further toward the base end than the insertion hole 16, and is configured to include the base end of the connector 12. The main body 17 is formed with a tapered hole 23 extending from the insertion hole 16 toward the base end, and a connection hole 24 extending from the tapered hole 23 toward the base end. The tapered hole 23 and the connection hole 24, together with the insertion hole 16, form part of the hole 14. The tapered hole 23 is enlarged toward the base end, and the connection hole 24 is open at the base end of the connector 12. The connection hole 24 is capable of connecting another connector.

[0033] Next, the extension part 18 will be described. The extension part 18 extends from the tip of the main body part 17 toward the tip side, and has a cylindrical shape. The extension length L1 of the extension part 18 is longer than the length L2 (length in the axial direction) of a joint part 21 that is joined to the main body part 17 in the catheter tube 11.

[0034] The extension portion 18 has an outer diameter that is substantially constant over the entire axial direction, whereas the inner diameter increases continuously from the base end to the tip end. The inner diameter of the extension portion 18 is larger than the diameter of the insertion hole 16, in other words, larger than the outer diameter of the catheter tube 11. The inner diameter of the tip end of the extension portion 18 is more than twice the outer diameter of the catheter tube 11. Since the inner diameter of the extension portion 18 increases toward the tip end, the extension portion 18 can also be called an increased diameter portion.

[0035] The inner surface of the extension portion 18 is a tapered surface 26 that is tapered and expands in diameter from the base end side toward the tip end side. The tapered surface 26 expands in diameter from the peripheral surface 16a of the insertion hole 16 toward the tip end side. Therefore, the tapered surface 26 and the peripheral surface 16a of the insertion hole 16 are continuous at their mutual boundary.

[0036] An inner space 25 is formed inside the extension portion 18. The inner space 25 communicates with the insertion hole 16 and constitutes a part of the hole portion 14. The inner space 25 is open toward the tip side. The tube lead-out portion 22 of the catheter tube 11, which is led out from the insertion hole 16 to the tip side, extends toward the tip side through the inner space 25. In this case, a part of the tube lead-out portion 22 is surrounded by the extension portion 18. The tube lead-out portion 22 and the extension portion 18 are separated from each other. The extension portion 18 corresponds to the "enclosing portion."

[0037] The inner surface of the tip of the extension portion 18 is a curved portion 28 that is curved so that the inner diameter increases toward the tip. The curved portion 28 smoothly connects the tip surface of the extension portion 18 and the tapered surface 26. The radius of curvature of the curved portion 28 is larger than the outer radius of the catheter tube 11. More specifically, the radius of curvature of the curved portion 28 is larger than the outer radius of the catheter tube 11 over the entire area of ​​the curved portion 28. Note that the radius of curvature of the curved portion 28 may be equal to or smaller than the outer radius of the catheter tube 11 in a part of the curved portion 28.

[0038] Next, the function of the extension portion 18 will be described with reference to Fig. 2. Fig. 2 is a cross-sectional view for explaining the function of the extension portion 18.

[0039] When the catheter 10 is introduced into the patient's body, as shown in Fig. 2(a), the tube lead-out portion 22 led out from the insertion hole 16 in the catheter tube 11 may be bent relative to the joint portion 21 where the catheter tube 11 is joined to the connector 12. In this case, according to the connector 12, the tube lead-out portion 22 abuts against the extension portion 18 of the connector 12, more specifically, along the tapered surface 26 of the extension portion 18. This abutment limits the amount of bending of the tube lead-out portion 22 relative to the joint portion 21. Therefore, it is possible to prevent the catheter tube 11 from kinking at the boundary between the tube lead-out portion 22 and the joint portion 21.

[0040] However, if the tube lead-out portion 22 is further bent while the bending (amount of bending) of the tube lead-out portion 22 is limited by the extension portion 18, the tube lead-out portion 22 may bend at the tip of the extension portion 18. In this regard, according to the connector 12 described above, the tube lead-out portion 22 is bent along the curved surface portion 28 as shown in Fig. 2(b). Therefore, it is possible to prevent the tube lead-out portion 22 from bending at the tip of the extension portion 18. This makes it possible to prevent the occurrence of kinking due to such bending.

[0041] According to the configuration of this embodiment described in detail above, the following excellent effects can be obtained.

[0042] When the bending amount of the tube lead-out portion 22 of the catheter tube 11 is limited by the surrounding portion, a load acts on the surrounding portion in the radially outward direction from the tube lead-out portion 22. In this regard, in the above embodiment, the surrounding portion is the cylindrical extension portion 18 extending from the main body portion 17 of the connector 12 toward the tip side, so that the above load acting on the extension portion 18 (enclosing portion) can be received in a stable state.

[0043] Furthermore, since the main body portion 17 and the extension portion 18 are integrally formed, it is possible to prevent the extension portion 18 from becoming detached from the main body portion 17 due to the above-mentioned load.

[0044] Since the inner surface of the extension portion 18 forms a tapered surface 26 that expands in diameter toward the tip side, when the tube leading-out portion 22 is bent, the tube leading-out portion 22 can abut along the tapered surface 26. This makes it possible to prevent stress concentration from occurring in the tube leading-out portion 22, and as a result, makes it possible to prevent kinking due to stress concentration.

[0045] Since the tapered surface 26 and the peripheral surface 16a of the insertion hole 16 are continuous, no step occurs at the boundary between the tapered surface 26 and the peripheral surface 16a of the insertion hole 16. In this case, it is possible to more reliably prevent the catheter tube 11 from bending at the boundary between the joint portion 21 inserted into the insertion hole 16 and joined to the connector 12, and the tube lead-out portion 22 led out from the insertion hole 16. Therefore, it is possible to more reliably prevent kinking from occurring at the boundary.

[0046] The connector 12 is optically transparent, and the catheter tube 11 is optically absorbing. In this case, the connector 12 and the catheter tube 11 can be laser welded at their interface by irradiating the interface between the connector 12 and the catheter tube 11 with laser light via the connector 12. This allows the thickness of the welded portion between the connector 12 and the catheter tube 11 to be relatively thin, and as a result, the difference in hardness between the joint portion 21 with the connector 12 (welded portion) and the tube lead-out portion 22 of the catheter tube 11 can be reduced. This makes it possible to further suppress the occurrence of kinks due to the difference in hardness.

[0047] Second Embodiment Next, a second embodiment will be described. In the second embodiment, the configuration of the extension part of the connector is different from that of the first embodiment. Therefore, the configuration of this embodiment will be described below, focusing on the differences. Figure 3 is a cross-sectional view showing the junction between the catheter tube 11 and the connector 32 in the catheter 30 and its surroundings.

[0048] 3, the catheter 30 of this embodiment, like the first embodiment, includes a catheter tube 11 and a connector 32 connected to the base end 11a of the catheter tube 11. Since the catheter tube 11 has the same configuration as in the first embodiment, it is denoted by the same reference numeral and description thereof will be omitted.

[0049] Similar to the first embodiment, the connector 32 has a main body 37 having an insertion hole 36 into which the base end 11a of the catheter tube 11 is inserted, and a cylindrical extension 38 extending from the main body 37 to the tip side. The configuration of the main body 37 is similar to that of the first embodiment, and therefore a description thereof will be omitted.

[0050] The inner diameter of the extension portion 38 is constant from the base end to the tip end. Therefore, the inner surface of the extension portion 38 is a non-tapered surface extending parallel to the axial direction. The inner diameter of the extension portion 38 is larger than the hole diameter of the insertion hole 16, in other words, larger than the outer diameter of the catheter tube 11. More specifically, the inner diameter of the extension portion 38 is more than twice the outer diameter of the catheter tube 11. Since the inner diameter of the extension portion 38 is constant from the base end to the tip end, the extension portion 38 can also be called a constant diameter portion.

[0051] As in the first embodiment, the extension length of the extension portion 38 is longer than the length of the joint portion 21 with the connector 12 of the catheter tube 11. A curved surface portion 48 is formed on the inner surface of the tip of the extension portion 38.

[0052] Next, the function of the extending portion 38 will be described with reference to Fig. 4. Fig. 4 is a cross-sectional view for explaining the function of the extending portion 38.

[0053] 4(a), when the catheter 30 is introduced into the body, the tube lead-out portion 22 of the catheter tube 11 is bent relative to the joint portion 21, so that the tube lead-out portion 22 abuts against the extending portion 38 of the connector 32. This abutment limits the amount of bending of the catheter tube 11. Therefore, as in the first embodiment, kinking of the catheter tube 11 at the boundary between the tube lead-out portion 22 and the joint portion 21 can be suppressed.

[0054] When the catheter 30 is introduced into the body, a force toward the base end side may act on the catheter tube 11. In that case, it is assumed that the tube lead-out portion 22 of the catheter tube 11 is bent near its base end so as to be convex (swell) in a direction perpendicular to the axial direction. In this regard, according to the connector 32, the inner diameter of the extension portion 38 is larger than the hole diameter of the insertion hole 16 from the base end to the tip end of the extension portion 38, so that the inner space 45 of the extension portion 38 is secured widely from the base end to the tip end. Therefore, as shown in FIG. 4(b), the vicinity of the base end of the tube lead-out portion 22 can be bent naturally in the inner space 45 of the extension portion 38, and as a result, it is possible to suppress kinking of the tube lead-out portion 22 near the base end.

[0055] Other Embodiments The present disclosure is not limited to the above embodiment, and may be implemented, for example, as follows.

[0056] (1) As shown in FIG. 5(a), the inner surface of the extension portion 52 of the connector 50 may include a plurality of tapered surfaces 54, 55. The tapered surfaces 54, 55 are adjacent to each other in the axial direction of the extension portion 52, with the tapered surface 54 being disposed on the base end side and the tapered surface 55 being disposed on the tip end side. The tapered surfaces 54, 55 are each enlarged in diameter from the base end side toward the tip end side and are continuous at the boundary between them. The tapered surface 54 on the base end side is continuous with the circumferential surface 16a of the insertion hole 16 at its base end. The tapered surfaces 54, 55 have different inclination angles with respect to the axial direction of the extension portion 52. Specifically, the inclination angle of the tapered surface 55 on the tip end side is larger than the inclination angle of the tapered surface 54 on the base end side.

[0057] According to the above configuration, since the inclination angle of the tapered surface 54 on the base end side is small, it is possible to further suppress bending of the tube lead-out portion 22 of the catheter tube 11 relative to the joint portion 21. Therefore, it is possible to further suppress the occurrence of kinking. Also, since the inclination angle of the tapered surface 55 on the tip end side is large, it is possible to sufficiently secure the bending amount of the tube lead-out portion 22 while suppressing the occurrence of kinking.

[0058] (2) As shown in Fig. 5(b), the inner surface of the extension portion 62 of the connector 60 may include a curved surface 63. In the example of Fig. 5(b), the curved surface 63 is formed over the entire axial area of ​​the extension portion 62. The curved surface 63 is formed so that the inner diameter increases from the base end side to the tip end side, and the curvature increases from the base end side to the tip end side. With this configuration, it is possible to obtain the same effect as the configuration of (1) above.

[0059] (3) As shown in FIG. 5(c), the extension portion 72 of the connector 70 may include a constant diameter portion 73 and an expanded diameter portion 74. In the example of FIG. 5(c), the constant diameter portion 73 is provided on the tip side of the extension portion 72, and the expanded diameter portion 74 is provided on the base end side of the extension portion 72. The constant diameter portion 73 has a constant inner diameter. Therefore, the inner surface of the constant diameter portion 73 is a non-tapered surface 76 that extends parallel to the axial direction of the extension portion 72. The inner diameter of the constant diameter portion 73 is larger than the hole diameter of the insertion hole 16.

[0060] The inner diameter of the expanded diameter portion 74 increases from the base end side toward the tip end side. Therefore, the inner surface of the expanded diameter portion 74 forms a tapered surface 77 that expands in diameter toward the tip end side. The tapered surface 77 is continuous with the peripheral surface 16a of the insertion hole 16 at its base end and with the non-tapered surface 76 at its tip end. In addition, the constant diameter portion 73 and the expanded diameter portion 74 have approximately the same length in the axial direction.

[0061] According to the above configuration, when a force toward the base end side acts on the catheter tube 11, the tube leading-out portion 22 can bend in the inner space 78 (mainly inside the constant diameter portion 73) of the extension portion 72. Therefore, it is possible to suppress the occurrence of kinking in such a case.

[0062] (4) As shown in Fig. 6(a), the extending portion 82 of the connector 80 may be provided with a protruding portion 85 that protrudes inward. The protruding portion 85 extends in an annular shape along the circumferential direction of the extending portion 82, and a plurality of protruding portions (specifically, two protruding portions) are provided at predetermined intervals in the axial direction of the extending portion 82. In this configuration, when the tube leading-out portion 22 of the catheter tube 11 is bent, the tube leading-out portion 22 can be brought into contact with the tip of the extending portion 82 and the tip of the protruding portion 85. Therefore, the stress that the tube leading-out portion 22 receives from the contact point with the connector 80 can be dispersed.

[0063] In the example of FIG. 6(a), the protruding heights of the protruding parts 85 are all the same, but as shown in FIG. 6(b), the protruding heights of the protruding parts 86, 87 may be different. In the example of FIG. 6(b), the protruding height of the protruding part 87 on the tip side is lower than that of the protruding part 86 on the base end side. That is, in the example of FIG. 6(b), the protruding part closer to the tip side has a lower protruding height. In this configuration, when the tube leading-out part 22 is bent, the tube leading-out part 22 can be easily brought into contact with the tip parts of the protruding parts 86, 87. Therefore, it is easy to obtain the effect of dispersing the stress that the tube leading-out part 22 receives from the contact point with the connector 80.

[0064] (5) As shown in Fig. 7, the base end 11a of the catheter tube 11 inserted into the insertion hole 36 of the connector 32 may have a non-jointed portion 92 that is not joined to the connector 32, located closer to the tip end than a joint portion 91 that is joined to the connector 32. In this case, the hardness difference (hardness change) between the joint portion 91 with the connector 32 and the tube lead-out portion 22 led out from the insertion hole 36 in the catheter tube 11 can be reduced. This makes it possible to suppress the occurrence of kinking due to the hardness difference.

[0065] (6) In the above embodiments, the connector 12, 32 has a main body 17, 37 and an extending portion 18, 38, but the configuration of the connector is not necessarily limited to this. For example, the connector may have a main body, an annular surrounding portion that is provided on the distal side of the main body and surrounds a part of the tube lead-out portion 22, and a rod-shaped connecting portion that connects the surrounding portion and the main body. In this case, too, when the tube lead-out portion 22 of the catheter tube 11 is bent, the amount of bending can be limited by the surrounding portion. Therefore, it is possible to prevent the catheter tube 11 from kinking at the boundary between the joint portion 21 and the tube lead-out portion 22.

[0066] (7) In each of the above embodiments, the base end 11a of the catheter tube 11 is laser welded to the connector 12, but a welding method other than laser welding may be used. Also, the base end 11a of the catheter tube 11 may be bonded to the connector 12 using an adhesive. In short, it is sufficient that the base end 11a of the catheter tube 11 is joined to the connector 12 by welding or adhesion.

[0067] Although the present disclosure has been described based on the embodiment, it is understood that the present disclosure is not limited to the embodiment or structure. The present disclosure also encompasses various modifications and modifications within the equivalent range. In addition, various combinations and forms, as well as other combinations and forms including only one element, more than one element, or less than one element, are also within the scope and concept of the present disclosure. [Explanation of symbols]

[0068] 10...catheter, 11...catheter tube, 12...connector, 16...insertion hole, 17...main body portion, 18...extension portion as surrounding portion, 22...tube outlet portion, 26...tapered surface, 28...curved surface portion, 30...catheter, 32...connector, 36...insertion hole, 37...main body portion, 38...extension portion.

Claims

1. A catheter tube; a connector connected to a proximal end of the catheter tube, the connector has an insertion hole into which the base end of the catheter tube is inserted, The insertion hole has a uniform hole diameter over the entire area in the axial direction, The connector is a catheter joined to the base end inserted into the insertion hole, a distal end portion of the base end inserted into the insertion hole that is not joined to the connector and that is further distal than a joint portion that is joined to the connector; The connector has a main body portion in which the insertion hole is formed, and an extension portion that extends from the main body portion toward a tip end and is provided on the tip end side of the insertion hole, the extension portion has a tubular shape and surrounds a part of a tube lead-out portion of the catheter tube led out from the insertion hole to a distal end side at a position spaced from the tube lead-out portion, The inner surface of the extension portion includes a tapered surface that expands in diameter toward the tip side, The inner surface of the tip of the extension portion is a curved portion formed so that the inner diameter increases toward the tip, the radius of curvature of the curved surface portion is greater than the outer radius of the catheter tube over the entire area of ​​the curved surface portion, A catheter, wherein the curved surface portion smoothly connects the tip surface of the extension portion and the tapered surface.

2. The catheter according to claim 1 , wherein the tapered surface is continuous with a circumferential surface of the insertion hole.

3. The extension portion has an inner diameter at a base end portion that is larger than the diameter of the insertion hole, The catheter according to claim 1 , wherein an inner diameter of the extension portion increases from the proximal end to the distal end.

4. The catheter according to claim 1 , wherein the connector is formed such that the main body and the extension are integrally formed.

5. The connector is formed to be optically transparent, the catheter tube is formed to have light absorbing properties; The catheter according to claim 1 , wherein the connector is joined to the proximal end of the catheter tube by welding.

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