Medical device

Abstract

A medical device 1 comprises a core shaft 5, a coil body 3 covering the distal-end part of the core shaft 5, and a distal end connection part 7a connecting the distal end of the coil body 3 and the distal end of the core shaft 5. The core shaft 5 has, on the distal-end side from the distal end of the coil body 3 in the distal end connection part 7a, a bulge part 9 having an outside diameter D2 greater than the inside diameter D1 of the coil body 3. The coil body 3 is provided with a first section C1 formed facing the bulge part 9, and a second section C2 formed on the base-end side of the first section C1 so as to be set apart from the first section C1. The distal end connection part 7a is packed between the first section C1 and the second section C2.

Description

medical devices

[0001] The present disclosure relates to medical devices.

[0002] Various guide wires that have been proposed are used to guide catheters and the like that are inserted into tubular organs or body tissues such as blood vessels, the digestive tract, and the urinary tract for treatment or examination.

[0003] For example, Patent Document 1 discloses a guide wire 10 including a core wire, a metal coil attached to the outer periphery of the tip of the core wire, and a brazed portion attached between the tip of the metal coil and the tip of the core wire.

[0004] Patent Document 1 further discloses that the brazing portion is made of a metal material such as gold brazing material, silver brazing material, or solder.

[0005] JP 2011-143077 A

[0006] The guidewire disclosed in Patent Document 1 has room for improvement in tensile strength. This problem is also common to medical devices other than guidewires.

[0007] A medical device according to the present disclosure comprises a core shaft, a coil body covering the distal end of the core shaft, and a connecting portion connecting the distal end of the coil body and the distal end of the core shaft, wherein the core shaft has a bulge portion within the connecting portion from the distal end of the coil body to the distal side, the bulge portion having an outer diameter larger than the inner diameter of the coil body, and the coil body comprises a first section formed opposite the bulge portion and a second section formed on the base end side of the first section and spaced apart from the first section, and the connecting portion is filled between the first section and the second section.

[0008] FIG. 1 is an overall schematic view of a guidewire according to a first embodiment of the present disclosure; FIG. 2 is an enlarged view of a distal end of the guidewire according to the first embodiment; FIG. 3 is a distal longitudinal cross-sectional view of a guidewire according to the first embodiment; FIG. 4 is a distal longitudinal cross-sectional view of a guidewire according to a second embodiment; FIG. 5 is a distal longitudinal cross-sectional view of a guidewire according to a third embodiment; FIG. 6 is a distal longitudinal cross-sectional view of a guidewire according to a fourth embodiment; FIG. 7 is a distal longitudinal cross-sectional view of a guidewire according to a fifth embodiment; FIG. 8 is a distal longitudinal cross-sectional view of a guidewire according to a sixth embodiment; FIG. 9 is a distal longitudinal cross-sectional view of a guidewire according to a seventh embodiment; FIG. 10 is a distal longitudinal cross-sectional view of a guidewire according to an eighth embodiment; FIG. 11 is a distal longitudinal cross-sectional view of a guidewire according to a ninth embodiment.

[0009] A guidewire according to an embodiment of the present disclosure will now be described with reference to the drawings. The guidewire is a medical device.

[0010] First Embodiment First, a first embodiment of the present disclosure will be described. The drawings used in this embodiment are exaggerated for ease of understanding, and the dimensions thereof differ from the actual dimensions.

[0011] In this embodiment and the embodiments described below, for convenience of explanation, the left side of the drawing in the longitudinal direction of the guidewire will be referred to as the distal end side, and the right side will be referred to as the proximal end side.

[0012] Fig. 1 is a schematic view of the entire guide wire according to a first embodiment of the present disclosure, Fig. 2 is an enlarged view of the distal end of the guide wire, and Fig. 3 is a longitudinal cross-sectional view of the distal end of the guide wire.

[0013] 1 to 3, the guidewire 1 of this embodiment includes a core shaft 5, a coil body 3, an end connection portion 7a (corresponding to the "connection portion" in this disclosure), a proximal end connection portion 7b, the core shaft 5, the coil body 3, and a coating agent 2. The coil body 3 covers the distal end of the core shaft 5. The distal end connection portion 7a is connected to the distal end of the coil body 3 and the distal end of the core shaft 5. The proximal end connection portion 7b is connected to the proximal end of the coil body 3 and the core shaft 5. The coating agent 2 covers the outer peripheries of the core shaft 5, the coil body 3, the distal connection portion 7a, and the proximal connection portion 7b. In FIGS. 1 and 2, the coating agent 2 is shown in cross section.

[0014] The core shaft 5 is an elongated flexible member having a generally circular cross section whose diameter decreases from the base end to the tip. The core shaft 5 includes a base end cylindrical portion 5d, an intermediate cylindrical portion 5c, a tip tapered portion 5b, and a tip cylindrical portion 5a. The base end cylindrical portion 5d has a generally cylindrical shape as a whole. The intermediate cylindrical portion 5c is formed continuously from the tip of the base end cylindrical portion 5d to the tip side. The intermediate cylindrical portion 5c has a smaller diameter than the base end cylindrical portion 5d. The tip tapered portion 5b is formed continuously from the tip of the intermediate cylindrical portion 5c to the tip side. The tip tapered portion 5b gradually decreases in diameter toward the tip. The tip cylindrical portion 5a is formed continuously from the tip of the tip tapered portion 5b to the tip side. The tip cylindrical portion 5a has a generally cylindrical shape.

[0015] There are no particular limitations on the material from which the core shaft 5 is made as long as it is a biocompatible material. Examples of materials that can be used to make the core shaft 5 include metal materials such as stainless steel, Ni-Ti alloys, and cobalt alloys, and resin materials such as polyethylene, polyethylene terephthalate, polypropylene, polyurethane, and polyvinyl chloride, and stainless steel is used in this embodiment.

[0016] The guide wire 1 of this embodiment includes a bulge 9 formed at the tip of the distal cylindrical portion 5a of the core shaft 5 within the distal connection portion 7a. The bulge 9 is formed from the distal end of the coil body 3 toward the distal side. The bulge 9 has an outer diameter D2 that is larger than the inner diameter D1 of the coil body 3.

[0017] There are no particular limitations on the material that forms the bulge 9 as long as it is a biocompatible material. Examples of materials that can be used to form the bulge 9 include metal materials such as platinum alloys, stainless steel, Ni-Ti alloys, and cobalt alloys, and resin materials such as polyethylene, polyethylene terephthalate, polypropylene, polyurethane, and polyvinyl chloride, and in this embodiment, a platinum alloy is used.

[0018] The coil body 3 is a hollow cylindrical coil body formed by winding at least one wire. The wire is either a metal wire or a resin wire. The tip of the coil body 3 is connected to the tip of the cylindrical tip portion 5a and the bulge portion 9 by a tip connecting portion 7a. The base end of the coil body 3 is connected to the tapered tip portion 5b of the core shaft 5 by a base connecting portion 7b.

[0019] The coil body 3 of this embodiment includes a first section C1 and a second section C2. The first section C1 is formed opposite the bulge 9. The wire in the first section C1 is wound helically around the core shaft 5. The second section C2 is formed on the proximal side of the first section C1 and spaced apart from the first section C1. The wire in the second section C2 is wound helically around the core shaft 5. The second section C2 is spaced apart from the first section C1 along the longitudinal direction of the core shaft 5 by a length X2 that is greater than the outer diameter X1 of the wire constituting the coil body 3. The tip connection portion 7a is filled between the first section C1 and the second section C2. The second section C2 extends from the tip connection portion 7a.

[0020] 3 does not show a wire portion located between the first section C1 and the second section C2 of the wires constituting the coil body 3. This unillustrated wire portion extends helically at a helical pitch greater than the helical pitch of the wires in the first section C1 and the second section C2, and connects the first section C1 and the second section C2. This unillustrated wire portion does not have to extend helically, and may extend along the longitudinal direction of the core shaft 5. The portion between the first section C1 and the second section C2 is referred to as a "connecting section L1."

[0021] The material of the wires constituting the coil body 3 is not particularly limited as long as it is a biocompatible material, similar to the core shaft 5. The material of the wires constituting the coil body 3 can be, for example, metal materials such as stainless steel, Ni-Ti alloys, and cobalt alloys, or resin materials such as polyethylene, polyethylene terephthalate, polypropylene, polyurethane, and polyvinyl chloride, and stainless steel is used in this embodiment.

[0022] As shown in FIG. 3 , a gap 4 is formed between the core shaft 5 and the coil body 3 .

[0023] As described above, the tip connecting portion 7a joins the tip of the coil body 3 to the tip of the core shaft 5. In the guide wire 1 of this embodiment, this tip connecting portion 7a improves the joining strength between the core shaft 5 and the coil body 3, thereby improving the tensile strength of the guide wire 1.

[0024] The guidewire 1 of this embodiment prevents the core shaft 5 from coming off the coil body 3 by utilizing the bulge 9 and the first section C1 formed opposite the bulge 9 within the distal connection portion 7a. The distal connection portion 7a is filled between the first section C1 and the second section C2. Therefore, the first section C1 is sandwiched between the bulge 9 and the material of the distal connection portion 7a filled on the proximal side of the first section C1. This improves the bonding strength between the core shaft 5 and the coil body 3, and also improves the tensile strength of the guidewire 1.

[0025] The first section C1 is a densely wound portion formed by winding the wire of the coil body 3 without leaving any gaps between them. Therefore, the first section C1 has higher rigidity than a section that is not densely wound. This prevents the first section C1 from coming off the distal end connecting portion 7a, further improving the joining strength between the core shaft 5 and the coil body 3 and further improving the tensile strength of the guide wire 1.

[0026] The second section C2 is spaced from the first section C1 along the longitudinal direction of the core shaft 5 by a length X2 that is greater than the outer diameter X1 of the wire constituting the coil body 3. This allows a greater amount of the tip connection portion 7a to be filled between the first section C1 and the second section C2. This further improves the bonding strength between the core shaft 5 and the coil body 3, thereby further improving the tensile strength of the guidewire 1.

[0027] The tip connecting portion 7a is formed by filling the material of the tip connecting portion 7a into the inside of the coil body 3. The manufacturer of the guidewire 1 can check the filling state of the tip connecting portion 7a inside the coil body 3 from between the first section C1 and the second section C2.

[0028] The material for forming the tip connecting portion 7a is not particularly limited as long as it is a biocompatible bonding material, and examples of materials that can be used for forming the tip connecting portion 7a include bonding materials made of resin materials such as silicone adhesives, acrylic adhesives, epoxy adhesives, and cyanoacrylate adhesives, and bonding materials made of metal materials such as gold-tin brazing material, silver-tin brazing material, gold-tin solder material, and silver-tin solder material, and in this embodiment, an epoxy adhesive is used.

[0029] As described above, the base end connecting portion 7b joins the base end of the coil body 3 and the core shaft 5. The same material as that of the tip connecting portion 7a can be used for the base end connecting portion 7b, and in this embodiment, an epoxy adhesive is used.

[0030] As described above, the coating agent 2 covers the outer periphery of the core shaft 5, the coil body 3, the distal connecting portion 7a, and the proximal connecting portion 7b. The material for the coating agent 2 is not particularly limited as long as it is a biocompatible joining material. Examples of materials that can be used for the coating agent 2 include polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, polyacrylamide, polyacrylic acid, sodium polyacrylate, poly(2-hydroxyethyl methacrylate), maleic anhydride copolymers, ethylene-vinyl alcohol copolymers, 2-methacryloyloxyethyl phosphorylcholine, (2-hydroxyethyl methacrylate)-styrene block copolymers, various synthetic polypeptides, collagen, hyaluronic acid, cellulose-based polymers, and mixtures thereof. In this embodiment, polyacrylamide is used. The above-mentioned 2-methacryloyloxyethyl phosphorylcholine may also be a copolymer thereof.

[0031] The guidewire 1 of this embodiment includes a core shaft 5, a coil body 3, and a distal connection portion 7a. The coil body 3 covers the distal end of the core shaft 5. The distal connection portion 7a connects the distal end of the coil body 3 to the distal end of the core shaft 5. The core shaft 5 has a bulge 9 within the distal connection portion 7a, extending from the distal end of the coil body 3 to the distal side. The bulge 9 has an outer diameter D2 larger than the inner diameter D1 of the coil body 3. The coil body 3 includes a first section C1 and a second section C2. The first section C1 is formed facing the bulge 9. The second section C2 is formed on the proximal side of the first section C1 and spaced apart from the first section C1. Therefore, the state of the distal connection portion 7a filling the interior of the coil body 3 can be confirmed from between the first section C1 and the second section C2. The distal connection portion 7a fills the space between the first section C1 and the second section C2. This improves the bonding strength between the core shaft 5 and the coil body 3, thereby improving the tensile strength of the guide wire 1. Even when a resin adhesive is used to prevent galvanic corrosion from occurring at the tip connection portion 7a, the tensile strength of the guide wire 1 can be ensured.

[0032] Second Embodiment A second embodiment of the present disclosure will be described. The drawings used in this embodiment are also exaggerated for ease of understanding, and the dimensions are different from the actual dimensions.

[0033] The overall schematic diagram and enlarged view of the tip of the guide wire of this embodiment are almost the same as those of the first embodiment, so the drawings will be omitted, and parts common to the first embodiment will be given the same symbols and will not be described.

[0034] The guidewire 10 of this embodiment differs from the guidewire 1 of the first embodiment in the shape of the tip connection portion that connects the tip of the coil body and the tip of the core shaft.

[0035] The distal end connection portion 7a in the guidewire 1 of the first embodiment connects the distal end of the coil body 3 to the distal end of the core shaft 5, including the bulge 9, the first section C1 of the coil body 3, and less than two turns of the second section C2. The bulge 9 is formed from the distal end of the coil body 3 toward the distal end. The first section C1 is formed opposite the bulge 9. The distal end connection portion 17a in the guidewire 10 of this embodiment connects the distal end of the coil body 13 to the distal end of the core shaft 5, including the bulge 9, the first section C11 of the coil body 13, and at least two turns of the second section C12. The bulge 9 is formed from the distal end of the coil body 13 toward the distal end. The first section C11 is formed opposite the bulge 9.

[0036] FIG. 4 is a longitudinal cross-sectional view of the distal end of the guide wire of the second embodiment.

[0037] 4 , the guidewire 10 of this embodiment includes a core shaft 5, a coil body 13, a distal connection portion 17a (corresponding to the "connection portion" in this disclosure), a proximal connection portion 7b, and a coating agent 2. The coil body 13 covers the distal end of the core shaft 5. The distal connection portion 17a is connected to the distal end of the coil body 13 and the distal end of the core shaft 5. The proximal connection portion 7b is connected to the proximal end of the coil body 13 and the core shaft 5. The coating agent 2 covers the outer peripheries of the core shaft 5, the coil body 13, the distal connection portion 17a, and the proximal connection portion 7b.

[0038] The guide wire 10 of this embodiment includes a bulge 9 formed at the tip of the distal cylindrical portion 5a of the core shaft 5 within the distal connection portion 17a. The bulge 9 is formed from the tip of the coil body 13 toward the distal end. The bulge 9 has an outer diameter D2 that is larger than the inner diameter D1 of the coil body 13.

[0039] The coil body 13 is a hollow cylindrical coil body formed by winding at least one wire. The wire is either a metal wire or a resin wire. The tip of the coil body 13 is connected to the tip of the cylindrical tip portion 5a and the bulge portion 9 by a tip connecting portion 17a. The base end of the coil body 13 is connected to the tapered tip portion 5b of the core shaft 5 by a base connecting portion 7b.

[0040] The coil body 13 of this embodiment includes a first section C11 and a second section C12. The second section C12 is spaced from the first section C11 along the longitudinal direction of the core shaft 5 by a length X12 that is greater than the outer diameter X1 of the wire constituting the coil body 13. The tip connection portion 17a is filled between the first section C11 and the second section C12. The second section C12 extends from the tip connection portion 17a. The portion between the first section C11 and the second section C12 is referred to as the "connecting section L11." The second section C12 is a tightly wound portion formed by winding the wire of the coil body 3 without any gaps. The second section C12 is located within the tip connection portion 17a by at least two turns. The portion of the second section C2 that is located within the tip connection portion 17a is referred to as the "tip embedded portion C12a." The first section C11 is formed opposite the bulging portion 9. The second section C12 is formed on the base end side of the first section C11 and spaced apart from the first section C11.

[0041] The wires constituting the coil body 13 can be made of the same material as the wires constituting the coil body 3 of the first embodiment, and in this embodiment, stainless steel is used.

[0042] As shown in FIG. 4 , a gap 4 is formed between the core shaft 5 and the coil body 13 .

[0043] As described above, the tip connection portion 17a joins the tip of the coil body 13 to the tip of the core shaft 5. As with the guide wire 1 of the first embodiment, the guide wire 10 of this embodiment improves the joining strength between the core shaft 5 and the coil body 13 by means of this tip connection portion 17a, thereby improving the tensile strength of the guide wire 10.

[0044] The guidewire 10 of this embodiment prevents the core shaft 5 from coming off the coil body 13 by utilizing the bulge 9 and the first section C11 formed opposite the bulge 9 within the distal connection portion 17a. The distal connection portion 17a is filled between the first section C11 and the second section C12. Therefore, the first section C11 is sandwiched between the bulge 9 and the material of the distal connection portion 17a filled on the proximal side of the first section C11. The distal connection portion 17a is sandwiched between the first section C11 and the distal embedded portion C12a. This further improves the bonding strength between the core shaft 5 and the coil body 13, thereby further improving the tensile strength of the guidewire 10.

[0045] The manufacturer of the guidewire 10 can check the state of the distal end connection portion 17a filling the inside of the coil body 13 from between the first section C11 and the second section C12.

[0046] The material of the tip connecting portion 17a can be the same as that of the tip connecting portion 7a of the first embodiment, and in this embodiment, an epoxy adhesive is used.

[0047] The guidewire 10 of this embodiment includes a core shaft 5, a coil body 13, and a distal connection portion 17a. The coil body 13 covers the distal end of the core shaft 5. The distal connection portion 17a connects the distal end of the coil body 13 to the distal end of the core shaft 5. The core shaft 5 has a bulge 9 within the distal connection portion 17a, extending from the distal end of the coil body 13 to the distal side. The bulge 9 has an outer diameter D2 larger than the inner diameter D1 of the coil body 13. The coil body 13 includes a first section C11 and a second section C12. The first section C11 is formed facing the bulge 9. The second section C12 is formed on the proximal side of the first section C11 and spaced apart from the first section C11. Therefore, the state of filling of the distal connection portion 17a into the interior of the coil body 13 can be confirmed between the first section C11 and the second section C12. The tip connection portion 17a is filled between the first section C11 and the second section C12, thereby improving the bonding strength between the core shaft 5 and the coil body 13 and improving the tensile strength of the guide wire 10. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connection portion 17a, the tensile strength of the guide wire 10 can be ensured.

[0048] According to the guide wire 10 of this embodiment, the second section C12 is a densely wound portion, and at least two turns of the second section C12 are located within the distal connection portion 17a. This further improves the joining strength between the core shaft 5 and the coil body 13, and further improves the tensile strength of the guide wire 10.

[0049] Third Embodiment A third embodiment of the present disclosure will be described. The drawings used in this embodiment are also exaggerated for ease of understanding, and the dimensions thereof differ from the actual dimensions.

[0050] The overall schematic diagram and enlarged view of the tip of the guide wire of this embodiment are almost the same as those of the first embodiment, so the drawings will be omitted, and parts common to the first and second embodiments will be given the same symbols and will not be described.

[0051] The guidewire 20 of this embodiment differs from the guidewire 1 of the first embodiment in the shape of the tip connection portion that connects the tip of the coil body and the tip of the core shaft.

[0052] The distal end connecting portion 7a in the guidewire 1 of the first embodiment connects the distal end of the coil body 3 to the distal end of the core shaft 5, including the bulging portion 9 and the first section C1 and part of the second section C2 of the coil body 3. The bulging portion 9 is formed from the distal end of the coil body 3 toward the distal side. The first section C1 is formed opposite the bulging portion 9. The distal end connecting portion 27a in the guidewire 20 of this embodiment connects the distal end of the coil body 23 to the distal end of the core shaft 5, including the bulging portion 9 and part of the first section C21, second section C22, and third section C23 of the coil body 23. The bulging portion 9 is formed from the distal end of the coil body 23 toward the distal side. The first section C21 is formed opposite the bulging portion 9. The third section C23 is formed on the proximal end side of the second section C22.

[0053] FIG. 5 is a longitudinal cross-sectional view of the distal end of a guide wire according to a third embodiment.

[0054] 5 , the guidewire 20 of this embodiment includes a core shaft 5, a coil body 23, a distal connection portion 27a (corresponding to the "connection portion" in this disclosure), a proximal connection portion 7b, and a coating agent 2. The coil body 23 covers the distal end of the core shaft 5. The distal connection portion 27a is connected to the distal end of the coil body 23 and the distal end of the core shaft 5. The proximal connection portion 7b is connected to the proximal end of the coil body 23 and the core shaft 5. The coating agent 2 covers the outer peripheries of the core shaft 5, the coil body 23, the distal connection portion 27a, and the proximal connection portion 7b.

[0055] The guide wire 20 of this embodiment includes a bulge 9 formed at the tip of the distal cylindrical portion 5a of the core shaft 5 within the distal connection portion 27a. The bulge 9 is formed from the tip of the coil body 23 toward the distal end. The bulge 9 has an outer diameter D2 that is larger than the inner diameter D1 of the coil body 23.

[0056] The coil body 23 is a hollow cylindrical coil body formed by winding at least one wire. The wire is either a metal wire or a resin wire. The tip of the coil body 23 is connected to the tip of the cylindrical tip portion 5a and the bulge portion 9 by a tip connecting portion 27a. The base end of the coil body 23 is connected to the tapered tip portion 5b of the core shaft 5 by a base connecting portion 7b.

[0057] The coil body 23 of this embodiment includes a first section C21, a second section C22, and a third section C23. The first section C21 is formed opposite the bulge 9. The wire in the first section C21 is wound helically around the core shaft 5 two times. The second section C22 is formed on the proximal side of the first section C21 and spaced apart from the first section C21. The wire in the second section C22 is wound helically around the core shaft 5 one time. The third section C23 is formed on the proximal side of the second section C22 and spaced apart from the second section C22. The wire in the third section C23 is wound helically around the core shaft 5 multiple times. The second section C22 is spaced apart from the first section C21 along the longitudinal direction of the core shaft 5 by a length X22 that is greater than the outer diameter X1 of the wire constituting the coil body 23. The third section C23 is spaced apart from the second section C22 along the longitudinal direction of the core shaft 5 by a length X23 that is greater than the outer diameter X1 of the wire constituting the coil body 23. The tip connection portion 27a is filled between the first section C21 and the second section C22, and also filled between the second section C22 and the third section C23.

[0058] 5 does not show the wire portion located between the first section C21 and the second section C22 and the wire portion located between the second section C22 and the third section C23. The wire portion (not shown) located between the first section C21 and the second section C22 extends helically at a helical pitch larger than the helical pitch of the wire in the first section C21 and the second section C22, connecting the first section C1 and the second section C2. The wire portion (not shown) located between the second section C22 and the third section C23 extends helically at a helical pitch larger than the helical pitch of the wire in the second section C22 and the third section C23, connecting the second section C22 and the third section C23. The portion between the first section C21 and the second section C22 is referred to as the "first connecting section L21." The portion between the second section C22 and the third section C23 is referred to as the "second connecting section L22." The wires in the first connecting section L21 do not have to extend helically, but may extend along the longitudinal direction of the core shaft 5. The wires in the second connecting section L22 do not have to extend helically, but may extend along the longitudinal direction of the core shaft 5.

[0059] The wires constituting the coil body 23 can be made of the same material as the wires constituting the coil body 3 of the first embodiment, and in this embodiment, stainless steel is used.

[0060] As shown in FIG. 5 , a gap 4 is formed between the core shaft 5 and the coil body 23 .

[0061] As described above, the tip connection portion 27a joins the tip of the coil body 23 to the tip of the core shaft 5. As with the guide wire 1 of the first embodiment, the guide wire 20 of this embodiment improves the joining strength between the core shaft 5 and the coil body 23 by means of this tip connection portion 27a, thereby improving the tensile strength of the guide wire 20.

[0062] The guidewire 20 of this embodiment prevents the core shaft 5 from coming off the coil body 23 by utilizing the bulge 9 and the first section C21 formed opposite the bulge 9 within the distal connection portion 27a. The distal connection portion 27a is filled between the first section C21 and the second section C22, and between the second section C22 and the third section C23. Therefore, the first section C21 is sandwiched between the bulge 9 and the material of the distal connection portion 27a filled on the proximal side of the first section C1. The second section C22 is sandwiched between the material of the distal connection portion 27a filled on the distal side of the second section C22 and the material of the distal connection portion 27a filled on the proximal side of the second section C22. This further improves the bonding strength between the core shaft 5 and the coil body 23, thereby further improving the tensile strength of the guidewire 20.

[0063] The manufacturer of the guide wire 20 can also check the filling state of the tip connection portion 27a inside the coil body 23 from between the first section C21 and the second section C22 and between the second section C22 and the third section C23.

[0064] The material of the tip connecting portion 27a can be the same as that of the tip connecting portion 7a of the first embodiment, and in this embodiment, an epoxy adhesive is used.

[0065] The guidewire 20 of this embodiment includes a core shaft 5, a coil body 23, and a distal connection portion 27a. The coil body 23 covers the distal end of the core shaft 5. The distal connection portion 27a connects the distal end of the coil body 23 to the distal end of the core shaft 5. The core shaft 5 has a bulge 9 within the distal connection portion 27a, extending from the distal end of the coil body 23 to the distal side. The bulge 9 has an outer diameter D2 larger than the inner diameter D1 of the coil body 23. The coil body 23 includes a first section C21 and a second section C22. The first section C21 is formed facing the bulge 9. The second section C22 is formed on the proximal side of the first section C21 and spaced apart from the first section C21. Therefore, the state of filling of the distal connection portion 27a into the interior of the coil body 23 can be confirmed between the first section C21 and the second section C22. The tip connection portion 27a is filled between the first section C21 and the second section C22, thereby improving the bonding strength between the core shaft 5 and the coil body 23 and improving the tensile strength of the guide wire 20. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connection portion 27a, the tensile strength of the guide wire 20 can be ensured.

[0066] According to the guidewire 20 of this embodiment, the coil body 23 includes a third section C23. The third section C23 is formed proximal to and spaced apart from the second section C22. This allows for better confirmation of the state of the distal connection portion 27a filling the interior of the coil body 23 from between the second section C22 and the third section C23. The distal connection portion 27a is filled between the second section C22 and the third section C23. This further improves the bonding strength between the core shaft 5 and the coil body 23, and further improves the tensile strength of the guidewire 20.

[0067] Fourth Embodiment A fourth embodiment of the present disclosure will be described. The drawings used in this embodiment are also exaggerated for ease of understanding, and the dimensions are different from the actual dimensions.

[0068] The overall schematic diagram and enlarged view of the tip of the guide wire of this embodiment are almost the same as those of the first embodiment, so the drawings will be omitted, and parts common to the first to third embodiments will be given the same symbols and will not be described.

[0069] The guidewire 30 of this embodiment differs from the guidewire 1 of the first embodiment in the shape of the tip connection portion that connects the tip of the coil body and the tip of the core shaft.

[0070] The distal connection portion 7a in the guidewire 1 of the first embodiment connects the distal end of the coil body 3 to the distal end of the core shaft 5, including the bulge 9, the first section C1 of the coil body 3, and less than two turns of the second section C2. The bulge 9 is formed from the distal end of the coil body 3 toward the distal side. The first section C1 is formed opposite the bulge 9. The distal connection portion 37a in the guidewire 30 of this embodiment connects the distal end of the coil body 33 to the distal end of the core shaft 5, including the bulge 9, and at least two turns of the first section C31, the second section C32, and the third section C33 of the coil body 33. The bulge 9 is formed from the distal end of the coil body 33 toward the distal side. The first section C31 is formed opposite the bulge 9. The second section C32 is formed on the proximal end side of the first section C31. The third section C33 is formed on the proximal end side of the second section C32.

[0071] FIG. 6 is a longitudinal cross-sectional view of the distal end of a guide wire according to a fourth embodiment.

[0072] 6 , the guidewire 30 of this embodiment includes a core shaft 5, a coil body 33, a distal connection portion 37a (corresponding to the "connection portion" in this disclosure), a proximal connection portion 7b, and a coating agent 2. The coil body 33 covers the distal end of the core shaft 5. The distal connection portion 37a is connected to the distal end of the coil body 33 and the distal end of the core shaft 5. The proximal connection portion 7b is connected to the proximal end of the coil body 33 and the core shaft 5. The coating agent 2 covers the outer peripheries of the core shaft 5, the coil body 33, the distal connection portion 37a, and the proximal connection portion 7b.

[0073] The guide wire 30 of this embodiment includes a bulge 9 formed at the tip of the distal cylindrical portion 5a of the core shaft 5 within the distal connection portion 37a. The bulge 9 is formed from the tip of the coil body 33 toward the distal end. The bulge 9 has an outer diameter D2 that is larger than the inner diameter D1 of the coil body 33.

[0074] The coil body 33 is a hollow cylindrical coil body formed by winding at least one wire. The wire is either a metal wire or a resin wire. The tip of the coil body 33 is connected to the tip of the cylindrical tip portion 5a and the bulge portion 9 by a tip connecting portion 37a. The base end of the coil body 33 is connected to the tapered tip portion 5b of the core shaft 5 by a base connecting portion 7b.

[0075] The coil body 33 of this embodiment includes a first section C31, a second section C32, and a third section C33. The first section C31 is formed opposite the bulge 9. The second section C32 is formed on the proximal side of the first section C31 and spaced apart from the first section C31. The second section C32 is spaced apart from the first section C31 along the longitudinal direction of the core shaft 5 by a length X32 that is greater than the outer diameter X1 of the wires that make up the coil body 33. The third section C33 is formed on the proximal side of the second section C32 and spaced apart from the second section C32. The third section C33 is spaced apart from the second section C32 along the longitudinal direction of the core shaft 5 by a length X33 that is greater than the outer diameter X1 of the wires that make up the coil body 33. The tip connection portion 37a is filled between the first section C31 and the second section C32, and also between the second section C32 and the third section C33. The third section C33 extends from the tip connection portion 37a. The portion between the first section C31 and the second section C32 is referred to as the "first connecting section L31." The portion between the second section C32 and the third section C33 is referred to as the "second connecting section L32." The third section C33 is a tightly wound portion formed by winding the wire of the coil body 3 without any gaps. The third section C33 is located within the tip connection portion 37a for at least two turns. The portion of the third section C33 located within the tip connection portion 37a is referred to as the "tip buried portion C33a."

[0076] The wires constituting the coil body 33 can be made of the same material as the wires constituting the coil body 3 of the first embodiment, and in this embodiment, stainless steel is used.

[0077] As shown in FIG. 6 , a gap 4 is formed between the core shaft 5 and the coil body 33 .

[0078] As described above, the tip connection portion 37a joins the tip of the coil body 33 to the tip of the core shaft 5. As with the guide wire 1 of the first embodiment, the guide wire 30 of this embodiment improves the joining strength between the core shaft 5 and the coil body 33 by means of this tip connection portion 37a, thereby improving the tensile strength of the guide wire 30.

[0079] The guidewire 30 of this embodiment prevents the core shaft 5 from coming off the coil body 33 by utilizing the bulge 9 and the first section C31 formed opposite the bulge 9 within the distal connection portion 37a. The distal connection portion 37a is filled between the first section C31 and the second section C32, and between the second section C32 and the third section C33. Therefore, the first section C31 is sandwiched between the bulge 9 and the material of the distal connection portion 37a filled on the proximal side of the first section C31. The second section C32 is sandwiched between the material of the distal connection portion 37a filled on the distal side of the second section C32 and the material of the distal connection portion 37a filled on the proximal side of the second section C32. This improves the bonding strength between the core shaft 5 and the coil body 33, and improves the tensile strength of the guidewire 30.

[0080] The manufacturer of the guide wire 30 can check the filling state of the tip connection portion 37a inside the coil body 33 from between the first section C31 and the second section C32 and between the second section C32 and the third section C33.

[0081] The material of the tip connecting portion 37a can be the same as that of the tip connecting portion 7a of the first embodiment, and in this embodiment, an epoxy adhesive is used.

[0082] The guidewire 30 of this embodiment includes a core shaft 5, a coil body 33, and a distal connection portion 37a. The coil body 33 covers the distal end of the core shaft 5. The distal connection portion 37a connects the distal end of the coil body 33 to the distal end of the core shaft 5. The core shaft 5 has a bulge 9 within the distal connection portion 37a, extending from the distal end of the coil body 33 to the distal side. The bulge 9 has an outer diameter D2 larger than the inner diameter D1 of the coil body 33. The coil body 33 includes a first section C31 and a second section C32. The first section C31 is formed facing the bulge 9. The second section C32 is formed on the proximal side of the first section C31 and spaced apart from the first section C31. Therefore, the state of filling of the distal connection portion 37a into the interior of the coil body 33 can be confirmed between the first section C31 and the second section C32. The tip connection portion 37a is filled between the first section C31 and the second section C32, thereby improving the bonding strength between the core shaft 5 and the coil body 33 and improving the tensile strength of the guide wire 30. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connection portion 37a, the tensile strength of the guide wire 30 can be ensured.

[0083] According to the guidewire 30 of this embodiment, the coil body 33 includes a third section C33. The third section C33 is formed proximal to and spaced apart from the second section C32. This allows for better confirmation of the state of the distal connection portion 37a filling the interior of the coil body 33 from between the second section C32 and the third section C33. The distal connection portion 37a is filled between the second section C32 and the third section C33. This further improves the bonding strength between the core shaft 5 and the coil body 33, thereby further improving the tensile strength of the guidewire 30.

[0084] According to the guidewire 30 of this embodiment, the third section C33 is a tightly wound portion. The third section C33 is located within the distal end connection portion 37a by at least two turns. This further improves the bonding strength between the core shaft 5 and the coil body 33, thereby further improving the tensile strength of the guidewire 30. Even when a resin adhesive is used to prevent galvanic corrosion at the distal end connection portion 37a, the tensile strength of the guidewire 30 can be further ensured.

[0085] Fifth Embodiment A fifth embodiment of the present disclosure will be described. The drawings used in this embodiment are also exaggerated for ease of understanding, and the dimensions thereof differ from the actual dimensions.

[0086] The overall schematic diagram and enlarged view of the tip of the guide wire of this embodiment are almost the same as those of the first embodiment, so the drawings will be omitted, and parts common to the first to fourth embodiments will be given the same symbols and will not be described.

[0087] The guidewire 40 of this embodiment differs from the guidewire 1 of the first embodiment in the shape of the bulging portion.

[0088] The bulging portion 9 in the guidewire 1 of the first embodiment is formed at the tip of the distal cylindrical portion 5a of the core shaft 5. The bulging portion 9 is formed separately from the core shaft 5. The bulging portion 49 in the guidewire 40 of this embodiment is formed by deforming the distal end of the distal cylindrical portion 45a of the core shaft 45.

[0089] 7 is a longitudinal cross-sectional view of the distal end of the guide wire according to the fifth embodiment, in which the distal cylindrical portion 45a of the core shaft 45 is partially shown in cross section.

[0090] 7 , the guidewire 40 of this embodiment includes a core shaft 45, a coil body 3, a distal connection portion 47a (corresponding to the "connection portion" in this disclosure), a proximal connection portion 7b, and a coating agent 2. The coil body 3 covers the distal end of the core shaft 45. The distal connection portion 47a is connected to the distal end of the coil body 3 and the distal end of the core shaft 45. The proximal connection portion 7b is connected to the proximal end of the coil body 3 and the core shaft 45. The coating agent 2 covers the outer peripheries of the core shaft 45, the coil body 3, the distal connection portion 47a, and the proximal connection portion 7b.

[0091] The core shaft 45 is an elongated flexible member having a generally circular cross section whose diameter decreases from the base end to the tip. The core shaft 45 includes a base end cylindrical portion 5d, an intermediate cylindrical portion 45c, a tip tapered portion 45b, and a tip cylindrical portion 45a. The base end cylindrical portion 5d has a generally cylindrical shape as a whole. The intermediate cylindrical portion 45c is formed continuously from the tip of the base end cylindrical portion 5d to the tip side. The intermediate cylindrical portion 5c has a smaller diameter than the base end cylindrical portion 5d. The tip tapered portion 45b is formed continuously from the tip of the intermediate cylindrical portion 45c to the tip side. The tip tapered portion 5b gradually decreases in diameter toward the tip. The tip cylindrical portion 45a is formed continuously from the tip of the tip tapered portion 45b to the tip side. The tip cylindrical portion 45a has a generally cylindrical shape.

[0092] The core shaft 45 can be made of the same material as the core shaft 5 of the first embodiment, and in this embodiment, stainless steel is used.

[0093] In the guidewire 40 of this embodiment, the bulging portion 49 is a loop portion L49 formed by the core shaft 45. The loop portion L49 is formed within the distal connection portion 47a by winding the distal end portion of the distal cylindrical portion 45a of the core shaft 45 in a substantially circular shape by one or more turns from the distal end of the coil body 3 toward the distal side around an axis intersecting with the central axis of the guidewire 40. The loop portion L49 has an outer diameter D3 that is larger than the inner diameter D1 of the coil body 3.

[0094] The loop portion L49 protrudes toward the tip end from the tip end of the coil body 3. The first and second turns of the tip cylindrical portion 45a that form the loop portion L49 overlap each other. The tip end 45ad of the core shaft 45 is not connected to the loop portion L49.

[0095] As shown in FIG. 7, a gap 4 is formed between the core shaft 45 and the coil body 3 .

[0096] As described above, the tip connection portion 47a joins the tip of the coil body 3 and the tip of the core shaft 5. As with the guide wire 1 of the first embodiment, the guide wire 40 of this embodiment improves the joining strength between the core shaft 45 and the coil body 3 by using this tip connection portion 47a, thereby improving the tensile strength of the guide wire 40.

[0097] The guidewire 40 of this embodiment prevents the core shaft 45 from coming off the coil body 3 by utilizing the bulge 49 and the first section C1 formed opposite the bulge 49 within the tip connecting portion 47a. The tip connecting portion 47a is filled between the first section C1 and the second section C2. Therefore, the first section C1 is sandwiched between the bulge 49 and the material of the tip connecting portion 47a filled on the proximal side of the first section C1. This improves the bonding strength between the core shaft 45 and the coil body 3, and also improves the tensile strength of the guidewire 40.

[0098] The manufacturer of the guide wire 40 can also check the state of the distal end connection portion 47a filling the inside of the coil body 3 from between the first section C1 and the second section C2.

[0099] The material of the tip connecting portion 47a can be the same as that of the tip connecting portion 7a of the first embodiment, and in this embodiment, an epoxy adhesive is used.

[0100] The guidewire 40 of this embodiment includes a core shaft 45, a coil body 3, and a distal connection portion 47a. The coil body 3 covers the distal end of the core shaft 45. The distal connection portion 47a connects the distal end of the coil body 3 to the distal end of the core shaft 45. The core shaft 45 has a bulge 49 within the distal connection portion 47a, extending from the distal end of the coil body 3 to the distal side. The bulge 49 has an outer diameter D3 larger than the inner diameter D1 of the coil body 3. The coil body 3 includes a first section C1 and a second section C2. The first section C1 is formed facing the bulge 49. The second section C2 is formed on the proximal side of the first section C1 and spaced apart from the first section C1. Therefore, the state of filling of the distal connection portion 47a into the interior of the coil body 3 can be confirmed between the first section C1 and the second section C2. The tip connection portion 47a is filled between the first section C1 and the second section C2, thereby improving the bonding strength between the core shaft 45 and the coil body 3 and improving the tensile strength of the guide wire 40. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connection portion 47a, the tensile strength of the guide wire 40 can be ensured.

[0101] According to the guidewire 40 of this embodiment, the bulge 49 is a loop portion L49 formed by the distal cylindrical portion 45a of the core shaft 45. Therefore, the bulge 49 can be easily formed. This improves the bonding strength between the core shaft 45 and the coil body 3, thereby improving the tensile strength of the guidewire 40. Even when a resin adhesive is used to prevent galvanic corrosion at the distal connection portion 47a, the tensile strength of the guidewire 40 can be ensured.

[0102] Sixth Embodiment A sixth embodiment of the present disclosure will be described. The drawings used in this embodiment are also exaggerated for ease of understanding, and the dimensions thereof differ from the actual dimensions.

[0103] The overall schematic diagram and enlarged view of the tip of the guide wire of this embodiment are almost the same as those of the first embodiment, so the drawings will be omitted, and parts common to the first to fifth embodiments will be given the same symbols and will not be described.

[0104] The guidewire 50 of this embodiment differs from the guidewire 1 of the first embodiment in the shape of the bulging portion.

[0105] The bulging portion 9 in the guidewire 1 of the first embodiment is formed at the tip of the distal cylindrical portion 5a of the core shaft 5. The bulging portion 9 is formed separately from the core shaft 5. The bulging portion 59 in the guidewire 50 of this embodiment is formed by deforming the distal end of the distal cylindrical portion 55a of the core shaft 55.

[0106] 8 is a longitudinal cross-sectional view of the distal end of the guide wire according to the sixth embodiment, in which the distal cylindrical portion 55a of the core shaft 55 is partially shown in cross section.

[0107] 8 , the guidewire 50 of this embodiment includes a core shaft 55, a coil body 3, a distal connection portion 57a ​​(corresponding to the "connection portion" in this disclosure), a proximal connection portion 7b, and a coating agent 2. The coil body 3 covers the distal end of the core shaft 55. The distal connection portion 57a ​​is connected to the distal end of the coil body 3 and the distal end of the core shaft 55. The proximal connection portion 7b is connected to the proximal end of the coil body 3 and the core shaft 55. The coating agent 2 covers the outer peripheries of the core shaft 55, the coil body 3, the distal connection portion 57a, and the proximal connection portion 7b.

[0108] The core shaft 55 is an elongated flexible member with a generally circular cross section whose diameter decreases from the base end to the tip. The core shaft 55 includes a base end cylindrical portion 5d, an intermediate cylindrical portion 55c, a tip tapered portion 55b, and a tip cylindrical portion 55a. The base end cylindrical portion 5d has a generally cylindrical shape as a whole. The intermediate cylindrical portion 55c is formed continuously from the tip of the base end cylindrical portion 5d to the tip side. The intermediate cylindrical portion 55c has a smaller diameter than the base end cylindrical portion 5d. The tip tapered portion 55b is formed continuously from the tip of the intermediate cylindrical portion 55c to the tip side. The tip tapered portion 55b gradually decreases in diameter toward the tip. The tip cylindrical portion 55a is formed continuously from the tip of the tip tapered portion 55b to the tip side. The tip cylindrical portion 55a has a generally cylindrical shape.

[0109] The core shaft 55 can be made of the same material as the core shaft 5 of the first embodiment, and in this embodiment, stainless steel is used.

[0110] In the guidewire 50 of this embodiment, the bulging portion 59 is a loop portion L59 formed by the core shaft 55. The loop portion L59 is formed within the distal connection portion 57a ​​by winding the distal end portion of the distal cylindrical portion 55a of the core shaft 55 from the distal end of the coil body 3 toward the distal side, in a substantially elliptical shape, one or more times around an axis intersecting the central axis of the guidewire 50. The loop portion L59 has a minor axis length D4 and a major axis length D5 that are greater than the inner diameter D1 of the coil body 3.

[0111] The loop portion L59 protrudes toward the tip end from the tip end of the coil body 3. The first and second turns of the tip cylindrical portion 55a that form the loop portion L59 overlap each other. The tip end 55ad of the core shaft 55 is not connected to the loop portion L59.

[0112] As shown in FIG. 8 , a gap 4 is formed between the core shaft 55 and the coil body 3 .

[0113] As described above, the tip connection portion 57a ​​joins the tip of the coil body 3 to the tip of the core shaft 55. As with the guide wire 1 of the first embodiment, the guide wire 50 of this embodiment improves the joining strength between the core shaft 55 and the coil body 3 by using this tip connection portion 57a, thereby improving the tensile strength of the guide wire 50.

[0114] The guidewire 50 of this embodiment prevents the core shaft 55 from coming off the coil body 3 by utilizing a bulge 59 and a first section C1 formed opposite the bulge 59 within the tip connecting portion 57a. The tip connecting portion 57a ​​is filled between the first section C1 and the second section C2. Therefore, the first section C1 is sandwiched between the bulge 59 and the material of the tip connecting portion 57a ​​filled on the proximal side of the first section C1. This improves the bonding strength between the core shaft 55 and the coil body 3, and thereby improves the tensile strength of the guidewire 50.

[0115] The manufacturer of the guide wire 50 can check the state of the distal end connection portion 57a ​​filling the inside of the coil body 3 from between the first section C1 and the second section C2.

[0116] The material of the tip connecting portion 57a ​​can be the same as that of the tip connecting portion 7a of the first embodiment, and in this embodiment, an epoxy adhesive is used.

[0117] The guidewire 50 of this embodiment includes a core shaft 55, a coil body 3, and a distal connection portion 57a. The coil body 3 covers the distal end of the core shaft 55. The distal connection portion 57a ​​connects the distal end of the coil body 3 to the distal end of the core shaft 55. The core shaft 55 has a bulge 59 within the distal connection portion 57a, extending from the distal end of the coil body 3 to the distal side. The bulge 59 has a minor axis length D4 and a major axis length D5 that are greater than the inner diameter D1 of the coil body 3. The coil body 3 includes a first section C1 and a second section C2. The first section C1 is formed facing the bulge 59. The second section C2 is formed on the proximal side of the first section C1 and spaced apart from the first section C1. Therefore, the filling state of the distal connection portion 57a ​​inside the coil body 3 can be confirmed between the first section C1 and the second section C2. The tip connection portion 57a ​​is filled between the first section C1 and the second section C2, thereby improving the bonding strength between the core shaft 55 and the coil body 3 and improving the tensile strength of the guide wire 50. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connection portion 57a, the tensile strength of the guide wire 50 can be ensured.

[0118] According to the guidewire 50 of this embodiment, the bulge 59 is an elliptical loop portion L59 formed by the distal cylindrical portion 55a of the core shaft 55. Therefore, the bulge 59 can be easily formed. This improves the bonding strength between the core shaft 55 and the coil body 3, thereby improving the tensile strength of the guidewire 50. Even when a resin adhesive is used to prevent galvanic corrosion at the distal connection portion 57a, the tensile strength of the guidewire 50 can be ensured.

[0119] Seventh Embodiment A seventh embodiment of the present disclosure will be described. The drawings used in this embodiment are also exaggerated for ease of understanding, and the dimensions thereof differ from the actual dimensions.

[0120] The overall schematic diagram and enlarged view of the tip of the guide wire of this embodiment are almost the same as those of the first embodiment, so the drawings will be omitted, and parts common to the first to sixth embodiments will be given the same symbols and will not be described.

[0121] The guidewire 60 of this embodiment differs from the guidewire 1 of the first embodiment in the shape of the bulging portion.

[0122] The bulging portion 9 in the guidewire 1 of the first embodiment is formed at the tip of the distal cylindrical portion 5a of the core shaft 5. The bulging portion 9 is formed separately from the core shaft 5. The bulging portion 69 in the guidewire 60 of this embodiment is formed by deforming the distal end of the distal cylindrical portion 65a of the core shaft 65.

[0123] 9 is a longitudinal cross-sectional view of the distal end of the guide wire according to the seventh embodiment, in which the distal cylindrical portion 65a of the core shaft 65 is partially shown in cross section.

[0124] 9 , the guidewire 60 of this embodiment includes a core shaft 65, a coil body 3, a distal connection portion 67a (corresponding to the "connection portion" in this disclosure), a proximal connection portion 7b, and a coating agent 2. The coil body 3 covers the distal end of the core shaft 65. The distal connection portion 67a is connected to the distal end of the coil body 3 and the distal end of the core shaft 65. The proximal connection portion 7b is connected to the proximal end of the coil body 3 and the core shaft 65. The coating agent 2 covers the outer peripheries of the core shaft 65, the coil body 3, the distal connection portion 67a, and the proximal connection portion 7b.

[0125] The core shaft 65 is an elongated flexible member with a generally circular cross section that tapers in diameter from the base end to the tip. The core shaft 65 includes a base end cylindrical portion 5d, an intermediate cylindrical portion 65c, a tip tapered portion 65b, and a tip cylindrical portion 65a. The base end cylindrical portion 5d is generally cylindrical overall. The intermediate cylindrical portion 65c is formed continuously from the tip of the base end cylindrical portion 5d toward the tip side. The intermediate cylindrical portion 65c has a smaller diameter than the base end cylindrical portion 5d. The tip tapered portion 65b is formed continuously from the tip of the intermediate cylindrical portion 65c toward the tip side. The tip tapered portion 65b gradually tapers in diameter toward the tip. The tip cylindrical portion 65a is formed continuously from the tip of the tip tapered portion 65b toward the tip side. The tip cylindrical portion 65a is generally cylindrical.

[0126] The core shaft 65 can be made of the same material as the core shaft 5 of the first embodiment, and in this embodiment, stainless steel is used.

[0127] In the guidewire 60 of this embodiment, the bulging portion 69 is a loop portion L69 formed by the core shaft 65. The loop portion L69 is formed within the distal connection portion 67a by bending the distal end portion of the distal cylindrical portion 65a of the core shaft 65 from the distal end of the coil body 3 toward the distal side into a substantially circular shape around an axis intersecting with the central axis of the guidewire 60. The loop portion L69 has an outer diameter D6 that is larger than the inner diameter D1 of the coil body 3.

[0128] The loop portion L69 protrudes toward the tip end from the tip end of the coil body 3. The first and second turns of the tip cylindrical portion 65a that form the loop portion L69 overlap each other. A tip end 65ad of the core shaft 65 is connected to the loop portion L69.

[0129] As shown in FIG. 9 , a gap 4 is formed between the core shaft 65 and the coil body 3 .

[0130] As described above, the tip connection portion 67a joins the tip of the coil body 3 and the tip of the core shaft 65. As with the guide wire 1 of the first embodiment, the guide wire 60 of this embodiment improves the joining strength between the core shaft 65 and the coil body 3 by using this tip connection portion 67a, thereby improving the tensile strength of the guide wire 60.

[0131] The guidewire 60 of this embodiment prevents the core shaft 65 from coming off the coil body 3 by utilizing the bulge 69 and the first section C1 formed opposite the bulge 69 within the tip connecting portion 67a. The tip connecting portion 67a is filled between the first section C1 and the second section C2. Therefore, the first section C1 is sandwiched between the bulge 69 and the material of the tip connecting portion 67a filled on the proximal side of the first section C1. This improves the bonding strength between the core shaft 65 and the coil body 3, and also improves the tensile strength of the guidewire 60.

[0132] The manufacturer of the guide wire 60 can check the state of the distal end connection portion 67a filling the inside of the coil body 3 from between the first section C1 and the second section C2.

[0133] The material of the tip connecting portion 67a can be the same as that of the tip connecting portion 7a of the first embodiment, and in this embodiment, an epoxy adhesive is used.

[0134] The guidewire 60 of this embodiment includes a core shaft 65, a coil body 3, and a distal end connecting portion 67a. The coil body 3 covers the distal end of the core shaft 65. The distal end connecting portion 67a connects the distal end of the coil body 3 to the distal end of the core shaft 65. The core shaft 65 has a bulge 69 within the distal end connecting portion 67a, extending from the distal end of the coil body 3 to the distal side. The bulge 69 has an outer diameter D6 that is larger than the inner diameter D1 of the coil body 3. The coil body 3 includes a first section C1 and a second section C2. The first section C1 is formed facing the bulge 69. The second section C2 is formed on the proximal side of the first section C1 and spaced apart from the first section C1. Therefore, the state of filling of the distal end connecting portion 67a into the interior of the coil body 3 can be confirmed between the first section C1 and the second section C2. The tip connection portion 67a is filled between the first section C1 and the second section C2, thereby improving the bonding strength between the core shaft 65 and the coil body 3 and improving the tensile strength of the guide wire 60. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connection portion 67a, the tensile strength of the guide wire 60 can be ensured.

[0135] According to the guidewire 60 of this embodiment, the bulge 69 is a loop portion L69 formed by the distal cylindrical portion 65a of the core shaft 65. This allows the bulge 69 to be easily formed. This improves the bonding strength between the core shaft 65 and the coil body 3, and thereby improves the tensile strength of the guidewire 60.

[0136] According to the guidewire 60 of this embodiment, the tip 65ad of the core shaft 65 is connected to the loop portion L69. This further improves the bonding strength between the core shaft 65 and the coil body 3, thereby further improving the tensile strength of the guidewire 60. Even when a resin adhesive is used to prevent galvanic corrosion from occurring at the tip connection portion 67a, the tensile strength of the guidewire 60 can be further ensured.

[0137] Eighth Embodiment An eighth embodiment of the present disclosure will be described. The drawings used in this embodiment are also exaggerated for ease of understanding, and the dimensions are different from the actual dimensions.

[0138] The overall schematic diagram and enlarged view of the tip of the guide wire of this embodiment are almost the same as those of the first embodiment, so the drawings will be omitted, and parts common to the first to seventh embodiments will be given the same symbols and will not be described.

[0139] The guidewire 70 of this embodiment differs from the guidewire 1 of the first embodiment in the shape of the bulging portion.

[0140] The bulging portion 9 in the guidewire 1 of the first embodiment is formed at the tip of the distal cylindrical portion 5a of the core shaft 5. The bulging portion 9 is formed separately from the core shaft 5. The bulging portion 79 in the guidewire 70 of this embodiment is formed by deforming the distal end of the distal cylindrical portion 75a of the core shaft 75.

[0141] 10 is a longitudinal cross-sectional view of the distal end of the guide wire according to the eighth embodiment, in which the distal cylindrical portion 75a of the core shaft 75 is partially shown in cross section.

[0142] 10 , the guidewire 70 of this embodiment includes a core shaft 75, a coil body 3, a distal connection portion 77a (corresponding to the "connection portion" in this disclosure), a proximal connection portion 7b, and a coating agent 2. The coil body 3 covers the distal end of the core shaft 75. The distal connection portion 77a is connected to the distal end of the coil body 3 and the distal end of the core shaft 75. The proximal connection portion 7b is connected to the proximal end of the coil body 3 and the core shaft 75. The coating agent 2 covers the outer peripheries of the core shaft 75, the coil body 3, the distal connection portion 77a, and the proximal connection portion 7b.

[0143] The core shaft 75 is an elongated flexible member with a generally circular cross section that tapers in diameter from the base end to the tip. The core shaft 75 includes a base end cylindrical portion 5d, an intermediate cylindrical portion 75c, a tip tapered portion 75b, and a tip cylindrical portion 75a. The base end cylindrical portion 5d is generally cylindrical overall. The intermediate cylindrical portion 75c is formed continuously from the tip of the base end cylindrical portion 5d toward the tip side. The intermediate cylindrical portion 75c has a smaller diameter than the base end cylindrical portion 5d. The tip tapered portion 75b is formed continuously from the tip of the intermediate cylindrical portion 75c toward the tip side. The tip tapered portion 75b gradually tapers in diameter toward the tip. The tip cylindrical portion 75a is formed continuously from the tip of the tip tapered portion 75b toward the tip side. The tip cylindrical portion 75a is generally cylindrical.

[0144] The core shaft 75 can be made of the same material as the core shaft 5 of the first embodiment, and in this embodiment, stainless steel is used.

[0145] In the guidewire 70 of this embodiment, the bulging portion 79 is a loop portion L79 formed by the core shaft 75. The loop portion L79 is formed within the distal connection portion 77a by winding the distal end portion of the distal cylindrical portion 75a of the core shaft 75 from the distal end of the coil body 3 toward the distal side, in a substantially elliptical shape, one or more times around an axis intersecting with the central axis of the guidewire 70. The loop portion L79 has a minor axis length D7 and a major axis length D8 that are greater than the inner diameter D1 of the coil body 3.

[0146] The loop portion L79 protrudes toward the tip side from the tip of the coil body 3. The first winding and the second winding of the tip cylindrical portion 75a overlap each other. The tip 75ad of the core shaft 55 is connected to the loop portion L79.

[0147] As shown in FIG. 10 , a gap 4 is formed between the core shaft 75 and the coil body 3 .

[0148] As described above, the tip connection portion 77a joins the tip of the coil body 3 to the tip of the core shaft 75. As with the guide wire 1 of the first embodiment, the guide wire 70 of this embodiment improves the joining strength between the core shaft 75 and the coil body 3 by using this tip connection portion 77a, thereby improving the tensile strength of the guide wire 70.

[0149] The guidewire 70 of this embodiment prevents the core shaft 75 from coming off the coil body 3 by utilizing a bulge 79 and a first section C1 formed opposite the bulge 79 within the tip connecting portion 77a. The tip connecting portion 77a is filled between the first section C1 and the second section C2. Therefore, the first section C1 is sandwiched between the bulge 79 and the material of the tip connecting portion 77a that is filled on the proximal side of the first section C1. This improves the bonding strength between the core shaft 75 and the coil body 3, and also improves the tensile strength of the guidewire 70.

[0150] The manufacturer of the guide wire 70 can also check the state of the distal end connection portion 77a filling the inside of the coil body 3 from between the first section C1 and the second section C2.

[0151] The material of the tip connecting portion 77a can be the same as that of the tip connecting portion 7a of the first embodiment, and in this embodiment, an epoxy adhesive is used.

[0152] The guidewire 70 of this embodiment includes a core shaft 75, a coil body 3, and a distal end connecting portion 77a. The coil body 3 covers the distal end of the core shaft 75. The distal end connecting portion 77a connects the distal end of the coil body 3 to the distal end of the core shaft 75. The core shaft 75 has a bulge 79 within the distal end connecting portion 77a, extending from the distal end of the coil body 3 to the distal side. The bulge 79 has a minor axis length D7 and a major axis length D8 that are greater than the inner diameter D1 of the coil body 3. The coil body 3 includes a first section C1 and a second section C2. The first section C1 is formed opposite the bulge 79. The second section C2 is formed on the proximal side of the first section C1 and spaced apart from the first section C1. Therefore, the filling state of the distal end connecting portion 77a inside the coil body 3 can be confirmed between the first section C1 and the second section C2. The tip connection portion 77a is filled between the first section C1 and the second section C2, thereby improving the bonding strength between the core shaft 75 and the coil body 3 and improving the tensile strength of the guide wire 70. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connection portion 77a, the tensile strength of the guide wire 50 can be ensured.

[0153] According to the guidewire 70 of this embodiment, the bulge 79 is an elliptical loop portion L79 formed by the distal cylindrical portion 75a of the core shaft 75. Therefore, the bulge 79 can be easily formed. This easily improves the bonding strength between the core shaft 75 and the coil body 3, and easily improves the tensile strength of the guidewire 70. Even when a resin adhesive is used to prevent galvanic corrosion at the distal connection portion 77a, the tensile strength of the guidewire 70 can be ensured.

[0154] According to the guidewire 70 of this embodiment, the tip 75ad of the core shaft 75 is connected to the loop portion L79. This further improves the bonding strength between the core shaft 75 and the coil body 3, thereby further improving the tensile strength of the guidewire 70. Even when a resin adhesive is used to prevent galvanic corrosion from occurring at the tip connection portion 77a, the tensile strength of the guidewire 70 can be further ensured.

[0155] Ninth Embodiment A ninth embodiment of the present disclosure will be described. The drawings used in this embodiment are also exaggerated for ease of understanding, and the dimensions thereof differ from the actual dimensions.

[0156] The overall schematic diagram and enlarged view of the tip of the guide wire of this embodiment are almost the same as those of the first embodiment, so the drawings will be omitted, and parts common to the first to eighth embodiments will be given the same symbols and will not be described.

[0157] The guidewire 80 of this embodiment differs from the guidewire 1 of the first embodiment in the shape of the vicinity of the distal end of the coil body.

[0158] The coil body 3 in the guidewire 1 of the first embodiment includes a first section C1 and a second section C2. The first section C1 is formed opposite the bulging portion 9. The second section C2 is formed on the proximal side of the first section C1 and spaced apart from the first section C1. The first section C1 is a tightly wound portion. As shown in FIG. 11 , the coil body 83 in the guidewire 80 of the present embodiment includes a first section C81, a second section C82, and a third section C83. The first section C81 is formed opposite the bulging portion 9. The second section C82 is formed on the proximal side of the first section C81 and spaced apart from the first section C81. The third section C83 is formed on the proximal side of the second section C82 and spaced apart from the second section C82. The first section C81 and the second section C82 are not tightly wound portions.

[0159] The wire in the first section C81 is wound helically one turn around the core shaft 5. The wire in the second section C82 is wound helically one turn around the core shaft 5. The wire in the third section C83 is wound helically multiple times around the core shaft 5. The third section C83 extends from the tip connecting portion 7a.

[0160] The second section C82 is spaced from the first section C81 along the longitudinal direction of the core shaft 5 by a length X82 that is smaller than the outer diameter X1 of the wires that make up the coil body 3. The third section C83 is spaced from the second section C82 along the longitudinal direction of the core shaft 5 by a length X83 that is smaller than the outer diameter X1 of the wires that make up the coil body 3. The lengths X82 and X83 may be larger than the outer diameter X1 of the wires that make up the coil body 3.

[0161] 11 does not show the wire portion located between the first section C81 and the second section C82 and the wire portion located between the second section C82 and the third section C83. The wire portion (not shown) located between the first section C81 and the second section C82 extends helically at a helical pitch larger than the helical pitch of the wire in the first section C81 and the second section C82, connecting the first section C81 and the second section C82. The wire portion (not shown) located between the second section C82 and the third section C83 extends helically at a helical pitch larger than the helical pitch of the wire in the second section C82 and the third section C83, connecting the second section C82 and the third section C83. The portion between the first section C81 and the second section C82 is referred to as the "first connecting section L81." The portion between the second section C82 and the third section C83 is referred to as the "second connecting section L82." The wires in the first connecting section L81 do not have to extend helically, but may extend along the longitudinal direction of the core shaft 5. The wires in the second connecting section L82 do not have to extend helically, but may extend along the longitudinal direction of the core shaft 5.

[0162] The guidewire 80 of this embodiment includes a core shaft 5, a coil body 83, and a distal connection portion 7a. The coil body 83 covers the distal end of the core shaft 5. The distal connection portion 7a connects the distal end of the coil body 83 to the distal end of the core shaft 5. The core shaft 5 has a bulge 9 within the distal connection portion 7a, extending from the distal end of the coil body 83 to the distal side. The bulge 9 has an outer diameter D2 larger than the inner diameter D1 of the coil body 83. The coil body 83 includes a first section C81 and a second section C82. The first section C81 is formed facing the bulge 9. The second section C82 is formed on the proximal side of the first section C81 and spaced apart from the first section C81. Therefore, the state of filling of the distal connection portion 7a inside the coil body 83 can be confirmed between the first section C81 and the second section C82. The tip connecting portion 7a is filled between the first section C81 and the second section C82. This improves the bond strength between the core shaft 5 and the coil body 83, thereby improving the tensile strength of the guidewire 80. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connecting portion 7a, the tensile strength of the guidewire 80 can be ensured. The coil body 83 includes a third section C83. The third section C83 is formed proximal to and spaced apart from the second section C82. This allows for better confirmation of the state of filling of the tip connecting portion 7a into the coil body 83 from between the second section C82 and the third section C83. The tip connecting portion 7a is filled between the second section C82 and the third section C83. This improves the bond strength between the core shaft 5 and the coil body 83, thereby improving the tensile strength of the guidewire 80. Even when a resin adhesive is used to prevent galvanic corrosion from occurring at the distal end connecting portion 7a, the tensile strength of the guide wire 80 can be further ensured.

[0163] The guidewire according to various embodiments of the present disclosure has been described above. The present disclosure is not limited to the above embodiments, and various modifications can be made without departing from the spirit and scope of the present disclosure.

[0164] For example, the distal connection portion 17a of the guidewire 10 of the second embodiment connects the distal end of the coil body to the distal end of the core shaft, including the bulge, the first section of the coil body, and at least two turns of the second section. The bulge is formed from the distal end of the coil body toward the distal side. The first section is formed opposite the bulge. This feature can also be applied to the guidewire 40 of the fifth embodiment, the guidewire 50 of the sixth embodiment, the guidewire 60 of the seventh embodiment, and the guidewire 70 of the eighth embodiment.

[0165] In this case, the bonding strength between the core shaft and the coil body can be further improved, and the tensile strength of the guide wire can be further improved. Even when a resin adhesive is used to prevent galvanic corrosion at the tip connection portion, the tensile strength of the guide wire can be further ensured.

[0166] The distal end connection portion 27a of the guidewire 20 of the third embodiment connects the distal end of the coil body to the distal end of the core shaft, including the bulge, and the first section, second section, and part of the third section of the coil body. The bulge is formed from the distal end of the coil body toward the distal side. The first section is formed opposite the bulge. This feature can also be applied to the guidewire 40 of the fifth embodiment, the guidewire 50 of the sixth embodiment, the guidewire 60 of the seventh embodiment, and the guidewire 70 of the eighth embodiment.

[0167] In this case, the state of filling of the tip connection portion into the coil body can be more clearly confirmed from between the first and second sections and between the second and third sections. The bonding strength between the core shaft and the coil body can be further improved, and the tensile strength of the guidewire can be further improved. Even when a resin adhesive is used to prevent galvanic corrosion from occurring at the tip connection portion, the tensile strength of the guidewire can be further ensured.

[0168] The distal end connection portion 37a of the guidewire 30 of the fourth embodiment connects the distal end of the coil body to the distal end of the core shaft, including the bulge and at least two turns of the first, second, and third sections of the coil body. The bulge is formed from the distal end of the coil body toward the distal side. The first section is formed opposite the bulge. This feature can also be applied to the guidewire 40 of the fifth embodiment, the guidewire 50 of the sixth embodiment, the guidewire 60 of the seventh embodiment, and the guidewire 70 of the eighth embodiment.

[0169] In this case, the state of filling of the tip connection portion into the coil body can be more clearly confirmed from between the first and second sections and between the second and third sections. The bonding strength between the core shaft and the coil body can be further improved, and the tensile strength of the guidewire can be further improved. Even when a resin adhesive is used to prevent galvanic corrosion from occurring at the tip connection portion, the tensile strength of the guidewire can be further ensured.

[0170] In the above-described embodiment, due to the size of the drawings, the close-wound portions of the coil body have been described as being formed by tightly winding a single wire. The spacing between the close-wound portions has been described as being slightly larger than the outer diameter of a single wire constituting the coil body along the longitudinal direction of the core shaft. Each close-wound portion may be formed by two or more wires. The spacing between the close-wound portions may be any length that is larger than the outer diameter of a single wire constituting the coil body along the longitudinal direction of the core shaft.

[0171] In the above-described embodiment, the coil body has been described as having a maximum of two tightly wound portions and a maximum of two connecting sections. The number of tightly wound portions and connecting sections in the coil body may be any number as long as the coil body can be used as a guidewire. The features of the above-described embodiment may also be applied to medical devices other than guidewires. Such medical devices include, for example, catheters and dilators.

Claims

1. A core shaft (5, 45, 55, 65, 75); a coil body (3, 13, 23, 33, 83) covering the tip of the core shaft (5, 45, 55, 65, 75); and a connection part (7a, 17a, 27a, 37a, 47a, 57a, 67a, 77a) connecting the tip of the coil body (3, 13, 23, 33, 83) and the tip of the core shaft (5, 45, 55, 65, 75), the core shaft (5, 45, 55, 65, 75) has, in the connection portion (7a, 17a, 27a, 37a, 47a, 57a, 67a, 77a), a bulge portion (9, 49, 59, 69, 79) having an outer diameter (D2, D3, D4, D6, D7) larger than an inner diameter (D1) of the coil body (3, 13, 23, 33, 83) from the tip of the coil body (3, 13, 23, 33, 83) toward the tip side, the coil body (3, 13, 23, 33, 83) comprises a first section (C1, C11, C21, C31, C81) formed opposite the bulge portion (9, 49, 59, 69, 79), and a second section (C2, C12, C22, C32, C82) formed away from the first section (C1, C11, C21, C31, C81) on the base end side of the first section (C1, C11, C21, C31, C81), A medical device (1, 10, 20, 30, 40, 50, 60, 70, 80), wherein the connection portion (7a, 17a, 27a, 37a, 47a, 57a, 67a, 77a) is filled between the first section (C1, C11, C21, C31, C81) and the second section (C2, C12, C22, C32, C82).

2. The medical device (1, 10, 20, 30, 40, 50, 60, 70) according to claim 1, wherein the first section (C1, C11, C21, C31) is a tightly wound section.

3. The medical device (1, 10, 20, 30, 40, 50, 60, 70) according to any one of claims 1 and 2, wherein the second section (C2, C12, C22, C32) is spaced apart from the first section (C1, C11, C21, C31) by a length (X2, X12, X22, X32) greater than the outer diameter (X1) of the wire constituting the coil body (3, 13, 23, 33) along the longitudinal direction of the core shaft (5, 45, 55, 65, 75).

4. A medical device (20, 30, 80) according to any one of claims 1 to 3, wherein the coil body (23, 33, 83) further comprises a third section (C23, C33, C83) formed on the proximal end side of the second section (C22, C32, C82) and spaced apart from the second section (C22, C32, C82), and the connecting portion (7a, 27a, 37a) is filled between the second section (C22, C32, C82) and the third section (C23, C33, C83).

5. A medical device (20, 30) according to claim 4, wherein the third section (C23, C33) is spaced apart from the second section (C22, C32) along the longitudinal direction of the core shaft (5) by a length (X23, X33) greater than the outer diameter (X1) of the wire constituting the coil body (23, 33).

6. A medical device (1, 10, 40, 50, 60, 70) according to any one of claims 1 to 5, wherein the second section (C2, C12) is a tightly wound section.

7. The medical device (10) according to claim 6, wherein the second section (C12) is located within the connection part for at least two turns.

8. A medical device (40, 50, 60, 70) according to any one of claims 1 to 7, wherein the bulge portion (49, 59, 69, 79) is a loop portion (L49, L59, L69, L79) formed by the core shaft (45, 55, 65, 75).

9. The medical device (50, 70) according to claim 8, wherein the loop portion (L59, L79) is elliptical.

10. A medical device (60, 70) according to any one of claims 8 and 9, wherein the distal end (65ad, 75ad) of the core shaft (65, 75) is connected to the loop portion (L69, L79).

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