Rotation transmission structure, catheter, and guide wire

Abstract

To provide a technology capable of improving rotation transmission performance of a rotation transmission member and adjusting rigidity of a rotation transmission structure.SOLUTION: A rotation transmission structure 20 includes a coil body 30 formed by winding of a wire 31, and a reinforcement body 40 that connects between adjacent wires 31 of the coil body 30. The reinforcement body 40 is provided such that rigidity in a prescribed area 21 in the longer direction is lower than rigidity in other areas 22 in the coil body 30 with the wires 31 connected to each other.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a rotational transmission structure, a catheter, and a guide wire.

Background Art

[0002] Patent Document 1 discloses a structure of a medical device including a coil including adjacent winding wires and a member connecting the adjacent winding wires of the coil. The member connecting the adjacent winding wires of the coil is arranged in a part of the region between the adjacent winding wires so as to be able to transmit torque between the adjacent winding wires.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, although improving the rotational transmission property of the rotational transmission member by a reinforcing body has been studied, adjusting the rigidity of the rotational transmission structure by the reinforcing body has not been considered.

[0005] An object of the present invention is to provide a technique capable of improving the rotational transmission property of a rotational transmission member and adjusting the rigidity of a rotational transmission structure.

Means for Solving the Problems

[0006] The rotational transmission structure of the present invention includes a coil body formed by winding wire elements, and a reinforcing body connecting between the adjacent wire elements of the coil body, and the reinforcing body is provided such that the rigidity of a predetermined region in the longitudinal direction is lower than the rigidity of other regions in the coil body in a state where the wire elements are connected.

[0007] According to the present invention, it is possible to improve the rotational transmission property of the rotational transmission structure as compared with the coil body not connected by the reinforcing body, and it is possible to adjust the rigidity of the rotational transmission structure by the reinforcing body.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Modes for Carrying Out the Invention

[0009] Preferred embodiments of the present invention will be described.

[0010] The reinforcing body is composed of a plurality of connecting parts provided for each part connecting the wire elements, and the plurality of connecting parts may be arranged less densely in the predetermined region than in the other regions. According to this configuration, the rigidity of the rotation transmission structure can be suitably adjusted by changing the arrangement of the plurality of connecting parts.

[0011] The plurality of connecting parts are arranged along a virtual spiral shape, and the pitch of the spiral shape in the predetermined region may be larger than the pitch of the spiral shape in the other regions. According to this configuration, the rigidity of the rotation transmission structure can be suitably adjusted by changing the pitch of the spiral shape.

[0012] The reinforcing body is composed of a plurality of connecting parts provided for each part connecting the wire elements, and the Young's modulus of the material of the connecting parts arranged in the predetermined region may be smaller than the Young's modulus of the material of the connecting parts arranged in the other regions. According to this configuration, the rigidity of the rotation transmission structure can be suitably adjusted by changing the Young's modulus of the material of the connecting parts.

[0013] The reinforcing body is composed of a plurality of connecting parts provided for each part connecting the wire elements, and the plurality of connecting parts may be arranged along a virtual spiral shape opposite to the winding direction of the coil body. According to this configuration, the rotation transmission property is better than that in the configuration where the plurality of connecting parts are arranged along a virtual spiral shape in the same direction as the winding direction of the coil body.

[0014] The reinforcing body is composed of a plurality of connecting parts provided for each part connecting the wire elements, and the plurality of connecting parts may be arranged along a virtual multi-strand spiral shape. According to this configuration, the range of rigidity that can be adjusted by the reinforcing body can be increased compared to the configuration where the plurality of connecting parts are arranged along a single spiral shape.

[0015] The outer diameter of the reinforcing body may be equal to or less than the maximum outer diameter of the coil body. According to this configuration, it is possible to suppress an increase in the outer diameter of the rotation transmission structure due to the provision of the reinforcing body.

[0016] The inner diameter of the reinforcing body may be equal to or greater than the minimum inner diameter of the coil body. According to this configuration, it is possible to suppress a decrease in the inner diameter of the rotation transmission structure due to the provision of the reinforcing body.

[0017] The catheter of the present invention is a catheter including a shaft portion reinforced by the above-described rotation transmission structure, and the predetermined region in the rotation transmission structure may be located closer to the distal end side than the other regions. According to this configuration, it is possible to realize a catheter having excellent rotation transmission performance and ensuring flexibility at the distal end portion.

[0018] The guide wire of the present invention is a guide wire including the above-described rotation transmission structure and a core shaft inserted into the lumen of the rotation transmission structure, and the predetermined region in the rotation transmission structure may be located closer to the distal end side than the other regions. According to this configuration, it is possible to realize a guide wire having excellent rotation transmission performance and ensuring flexibility at the distal end portion.

[0019] <Embodiment 1> Next, Embodiment 1 embodying the present invention will be described with reference to FIGS. 1 to 6. In FIG. 1, the right side in the drawing is the distal end side (distal side) inserted into the body, and the left side is the proximal end side (proximal side, base end side) operated by a technician such as a doctor.

[0020] FIG. 1 is an explanatory view showing a medical catheter (a kind of medical device) 10 including a rotation transmission structure 20. The catheter 10 includes a shaft portion 11, a tip chip 12 provided on the distal end side of the shaft portion 11, and a connector 13 provided on the proximal end side of the shaft portion 11. The rigidity of the distal end portion 11A of the shaft portion 11 is lower than the rigidity of the portion other than the distal end portion 11A. The portion other than the distal end portion 11A in the shaft portion 11 is a portion also referred to as the main body portion or the proximal end portion of the shaft portion 11.

[0021] As shown in FIG. 2, the shaft portion 11 has, from the inside in order, an inner layer 14, a rotation transmission structure 20 as a reinforcing member, a middle layer 15, and an outer layer 16.

[0022] The inner layer 14 is formed of resin and constitutes a lumen 17 for inserting a guide wire or other catheter therein. The resin material forming the inner layer 14 is not particularly limited, but in the present embodiment, PTFE (polytetrafluoroethylene) is used. A rotation transmission structure 20 as a reinforcing member is formed on the outer periphery of the inner layer 14. The configuration of the rotation transmission structure 20 will be described later.

[0023] A middle layer 15 made of resin is formed on the outer periphery of the rotation transmission structure 20 and covers the inner layer 14 and the rotation transmission structure 20. The resin material forming the middle layer 15 is not particularly limited, and polyamide, polyamide elastomer, polyester, polyurethane, etc. are used.

[0024] As shown in the cross-sectional view of FIG. 3, the middle layer 15 covers the shaft portion 11 except for the tip 12. The middle layer 15 is adhered to the inner layer 14 at the gap of the rotation transmission structure 20 (in other words, the gap 32 between adjacent element wires 31).

[0025] An outer layer 16 made of resin is formed on the outer periphery of the middle layer 15 and covers the middle layer 15. The resin material forming the outer layer 16 is not particularly limited, and like the middle layer 15, polyamide, polyamide elastomer, polyester, polyurethane, etc. are used. The outer layer 16 may be configured to use resin materials with different hardnesses so as to be flexible toward the tip portion 11A side in the shaft portion 11. For example, the first outer layer 16A covering the tip portion 11A may be formed of a resin that is more flexible than the second outer layer 16B covering the portion other than the tip portion 11A.

[0026] As shown in FIG. 4, the rotational transmission structure 20 includes a coil body 30 and a reinforcing body 40. The rotational transmission structure 20 has a first region 21 and a second region 22 located on the proximal side of the first region 21. The first region 21 corresponds to a predetermined region in the longitudinal direction. The second region 22 corresponds to other regions. Specifically, the first region 21 constitutes the tip portion 11A of the shaft portion 11. The second region 22 constitutes the portion of the shaft portion 11 other than the tip portion 11A.

[0027] As shown in FIGS. 4 and 5, the coil body 30 is formed by winding wire elements 31. The wire element 31 is a flat wire. The cross-sectional shape of the wire element may be substantially rectangular, or may be substantially circular or polygonal. The diameter of the wire element 31 is substantially constant over the entire length. The material of the wire element 31 is not particularly limited, but materials having biocompatibility and being corrosion-resistant, such as stainless alloy (SUS), nickel-titanium alloy (NiTi), titanium (Ti), platinum (Pt), tungsten (W), gold (Au), silver (Ag), etc., are preferable.

[0028] The coil body 30 is wound in a helical shape. The outer diameter and inner diameter of the coil body 30 are substantially constant over the entire length. In a state where the coil body 30 is not connected by the reinforcing body 40, the bending rigidity and torsional rigidity are substantially constant over the entire length. The coil body 30 has adjacent wire elements 31 not in contact with each other, so-called sparse winding. In other words, a gap 32 is formed between adjacent wire elements 31 of the coil body 30.

[0029] The reinforcing body 40 is a member that connects between adjacent wire elements 31 of the coil body 30. The material of the reinforcing body 40 is not particularly limited, and it may be the same material as the coil body 30 or a different material. Examples of the material of the reinforcing body 40 include metal materials such as stainless steel (SUS), nickel-titanium alloy (NiTi), titanium (Ti), nickel-chromium alloy (NiCr), metal brazing materials, resin adhesives, etc. Further, the reinforcing body 40 may be formed of a part of the material constituting the coil body 30 by welding between the wire elements 31. In the present embodiment, the reinforcing body 40 is formed of the same material throughout the entire area.

[0030] The reinforcing body 40 is provided in the coil body 30 in a state where the strands 31 are connected such that the rigidity of the first region 21 is lower than the rigidity of the second region 22. This reinforcing body 40 is provided in both the first region 21 and the second region 22. The rigidity of the first region 21 is higher than the rigidity of the coil body 30 not connected by the reinforcing body 40 and lower than the rigidity of the second region 22. The rotational transmission structure 20 gradually decreases in rigidity from the second region 22 toward the first region 21. Examples of the index of rigidity include bending rigidity and torsional rigidity.

[0031] The reinforcing body 40 is composed of a plurality of connection parts 41 and 42 provided for each part connecting the strands 31. Among the plurality of connection parts 41 and 42, the plurality of connection parts 41 are arranged in the first region 21, and the plurality of connection parts 42 are arranged in the second region 22.

[0032] The plurality of connection parts 41 and 42 are arranged more sparsely in the first region 21 than in the second region 22. In other words, the density of the plurality of connection parts 41 is smaller than the density of the plurality of connection parts 42. The density of the plurality of connection parts 41 can be obtained, for example, as the mass of the plurality of connection parts 41 per unit length of the coil body 30. At this time, the unit length of the coil body 30 may be appropriately set according to the distribution of the plurality of connection parts 41 and 42. The density of the plurality of connection parts 42 can be obtained in the same manner as the density of the plurality of connection parts 41. The density of the plurality of connection parts 41 and 42 can be adjusted by changing the number, size, and arrangement (the pitch of the helical shape and the number of helical shape lines described later) of the connection parts.

[0033] The plurality of connection parts 41 and 42 are arranged along a virtual single helical shape S1. This helical shape S1 is in the opposite direction to the winding direction of the coil body 30. For example, when the coil body 30 is wound in the counterclockwise direction (S winding) toward the tip, the plurality of connection parts 41 and 42 are arranged along a virtual helical shape S1 that is wound in the clockwise direction (Z winding) toward the tip.

[0034] The pitch P1 of the spiral shape S1 in the first region 21 is larger than the pitch P2 of the spiral shape S1 in the second region 22. In other words, the rotational transmission structure 20 has a configuration in which the pitch of the spiral shape S1 is variable in order to adjust the rigidity. The pitch of the spiral shape S1 is the dimension between the turns of the spiral shape S1 in the longitudinal direction of the rotational transmission structure 20. The pitch P1 of the spiral shape S1 in the first region 21 gradually increases toward the tip side.

[0035] The size of the connecting portion 41 is smaller than the size of the connecting portion 42. Specifically, in the winding direction of the wire element 31, the dimension of the connecting portion 41 is smaller than the dimension of the connecting portion 42. The sizes of the plurality of connecting portions 41 and 42 gradually decrease toward the tip side.

[0036] As shown in FIG. 6, the outer diameter of the reinforcing body 40 is equal to or less than the maximum outer diameter of the coil body 30. In other words, the reinforcing body 40 is disposed on the inner peripheral side of a virtual cylindrical surface 34A that circumscribes the outer peripheral surface 34 of the coil body 30. Further, the inner diameter of the reinforcing body 40 is equal to or greater than the minimum inner diameter of the coil body 30. In other words, the reinforcing body 40 is disposed on the outer peripheral side of a virtual cylindrical surface 35A that inscribes the inner peripheral surface 35 of the coil body 30. That is, the reinforcing body 40 is configured to be disposed in the gap 32 between the wire elements 31 where the plurality of connecting portions 41 and 42 are adjacent to each other. The outer surface of the reinforcing body 40 is flush with the outer peripheral surface 34 of the coil body 30. The inner surface of the reinforcing body 40 is flush with the inner peripheral surface 35 of the coil body 30. Note that the size and arrangement of the reinforcing body 40 are not limited to this. For example, in the radial direction of the coil body 30, a configuration may be adopted in which the dimensions of the reinforcing body 40 (connecting portions 41 and 42) are smaller than the thickness dimension of the wire element 31, and the connecting portions 41 and 42 are located between the outer peripheral surface 34 and the inner peripheral surface 35.

[0037] Next, the effects of the present embodiment will be described.

[0038] According to the rotational transmission structure 20 of the present embodiment, the rotational transmission property of the rotational transmission structure 20 can be improved as compared with the coil body not connected by the reinforcing body 40, and the rigidity of the rotational transmission structure 20 can be adjusted by the reinforcing body 40. For example, according to the rotational transmission structure 20, the rigidity is increased at portions other than the tip portion 11A in the shaft portion 11 to improve the operability of the catheter 10, and the flexibility of the rotational transmission structure 20 can be ensured at the tip portion 11A in the shaft portion 11.

[0039] In order to confirm the effect of the present embodiment, the pitch of the helical shape in the reinforcing body was changed, and the bending rigidity of the rotational transmission structure was obtained by simulation. From this result, it was confirmed that when the pitch of the helical shape in the reinforcing body is increased, the bending rigidity decreases. Also, the pitch of the helical shape in the reinforcing body was changed, and the torsional rigidity of the rotational transmission structure was obtained by simulation. From this result, it was confirmed that when the pitch of the helical shape in the reinforcing body is increased, the torsional rigidity decreases. Furthermore, it was confirmed that when the pitch is increased stepwise, under predetermined conditions, the bending rigidity tends to be smaller than the torsional rigidity. From this result, for example, it was suggested that the reinforcing body 40 can realize the bending rigidity and torsional rigidity according to the medical device to which the rotational transmission structure 20 is applied, such as reducing the bending rigidity while ensuring the torsional rigidity according to the part of the rotational transmission structure 20.

[0040] Also, in a configuration in which a slot pattern is formed on the side surface of the tubular member to adjust the rigidity of the rotational transmission structure, when a rotational force is applied to the rotational transmission structure, stress concentrates on the opening edge of the slot formed in the tubular member, and there is a concern that the rotational transmission structure may break or the like. On the other hand, in the present embodiment, when a rotational force is applied to the rotational transmission structure 20, even if the connection between the wire elements 31 in the coil body 30 is partially disengaged, breakage of the coil body 30 itself can be avoided.

[0041] In this embodiment, the plurality of connecting portions 41 and 42 are arranged more sparsely in the first region 21 than in the second region 22. Therefore, by changing the arrangement of the plurality of connecting portions 41 and 42, the rigidity of the rotational transmission structure 20 can be suitably adjusted.

[0042] In this embodiment, the pitch P1 of the helical shape S1 in the first region 21 is larger than the pitch P2 of the helical shape S1 in the second region 22. Therefore, by changing the pitches P1 and P2 of the helical shape S1, the rigidity of the rotational transmission structure 20 can be suitably adjusted.

[0043] In this embodiment, the plurality of connecting portions 41 and 42 are arranged along a virtual helical shape S1 opposite to the winding direction of the coil body 30. Therefore, the rotational transmission performance is better than that in the configuration where the plurality of connecting portions 41 and 42 are arranged along a virtual helical shape S1 in the same direction as the winding direction of the coil body 30.

[0044] In this embodiment, the outer diameter of the reinforcing body 40 is equal to or less than the maximum outer diameter of the coil body 30. Therefore, it is possible to suppress an increase in the outer diameter of the rotational transmission structure 20 due to the provision of the reinforcing body 40. The inner diameter of the reinforcing body 40 is equal to or greater than the minimum inner diameter of the coil body 30. Therefore, it is possible to suppress a decrease in the inner diameter of the rotational transmission structure 20 due to the provision of the reinforcing body 40. Further, in this embodiment, the reinforcing body 40 is arranged in the gap 32 between the wire elements 31. Therefore, when the rotational transmission structure 20 is pushed in, the pushing force can be more easily transmitted to the tip side, and the pushability of the rotational transmission structure 20 can be further improved.

[0045] The catheter 10 of this embodiment is a catheter 10 including a shaft portion 11 reinforced by the above-described rotational transmission structure 20, and the first region 21 in the rotational transmission structure 20 is located closer to the tip side than the second region 22. Therefore, it is possible to realize a catheter 10 having excellent rotational transmission performance and ensuring the flexibility of the tip portion 11A.

[0046] <Embodiment 2> The rotational transmission structure 220 according to Embodiment 2 has a different configuration of the reinforcing member from that of Embodiment 1 as shown in FIGS. 7 and 8. The same components as those in Embodiment 1 are denoted by the same reference numerals, and redundant descriptions are omitted.

[0047] The rotational transmission structure 220 includes a coil body 30 and a reinforcing member 240. The rotational transmission structure 220 has a first region 21, a second region 22 located closer to the proximal end side than the first region 21, and an intermediate region 23 located between the first region 21 and the second region 22. The first region 21 corresponds to a predetermined region in the longitudinal direction. The second region 22 corresponds to another region. Specifically, the first region 21 constitutes the tip end portion 11A of the shaft portion 11. The second region 22 constitutes the proximal end portion of the shaft portion 11.

[0048] The reinforcing member 240 is provided in the coil body 30 in a state where the strands 31 are connected so that the rigidity of the first region 21 is lower than the rigidity of the second region 22. The reinforcing member 240 is provided in the first region 21, the second region 22, and the intermediate region 23. The rigidity of the first region 21 is higher than the rigidity of the coil body 30 without the reinforcing member 240 and lower than the rigidity of the second region 22 and the intermediate region 23. The rigidity of the intermediate region 23 is lower than the rigidity of the second region 22. The rotational transmission structure 220 has a multi-step decrease in rigidity from the second region 22 toward the first region 21. Examples of the rigidity index include bending rigidity and torsional rigidity.

[0049] The reinforcing member 240 is constituted by a plurality of connection portions 241, 242, 243 provided for each portion connecting the strands 31. Among the plurality of connection portions 241, 242, 243, the plurality of connection portions 241 are arranged in the first region 21, and the plurality of connection portions 242 are arranged in the second region 22. The plurality of connection portions 243 are arranged in the intermediate region 23. The plurality of connection portions 241 correspond to the connection portions arranged in a predetermined region. The plurality of connection portions 242 correspond to the connection portions arranged in another region.

[0050] The plurality of connection portions 241, 242, 243 are arranged along virtual four helical shapes S1 to S4. Each of these four helical shapes S1 to S4 is in the opposite direction to the winding direction of the coil body 30. For example, when the coil body 30 is wound in the counterclockwise direction (S winding) toward the tip, the plurality of connection portions 241, 242, 243 are arranged along virtual helical shapes S1 to S4 that are wound in the clockwise direction (Z winding) toward the tip. The four helical shapes S1 to S4 are arranged such that they are shifted from each other by 90° in the circumferential direction. The density of the plurality of connection portions 241 is equal to the density of the plurality of connection portions 242.

[0051] The Young's modulus of the material forming the connection portion 241 is smaller than the Young's modulus of the material forming the connection portion 242. Specifically, the plurality of connection portions 241 are made of the same first material. In FIG. 8, the connection portions formed of the first material are represented in black. The plurality of connection portions 242 are made of the same second material. In FIG. 8, the connection portions formed of the second material are represented in white. The Young's modulus of this first material is smaller than the Young's modulus of the second material. Half of the plurality of connection portions 243 are made of the first material, and the remaining half of the plurality of connection portions 243 are made of the second material. The plurality of connection portions 243 made of the first material are arranged along two of the four helical shapes S1 and S3. The plurality of connection portions 243 made of the second material are arranged along the other two of the four helical shapes S2 and S4.

[0052] Next, the effects of the present embodiment will be described.

[0053] According to the rotational transmission structure 220 of the present embodiment, the rotational transmission performance can be improved as compared with the coil body not connected by the reinforcing body 240, and the rigidity of the rotational transmission structure 220 can be adjusted by the reinforcing body 240. For example, according to the rotational transmission structure 220, the rigidity can be increased at portions other than the tip portion 11A in the shaft portion 11 to improve the operability of the catheter 10, and the flexibility of the rotational transmission structure 220 can be ensured at the tip portion 11A in the shaft portion 11.

[0054] In order to confirm the effects of this embodiment, the Young's modulus of the material forming the plurality of connection portions was changed, and the bending rigidity of the rotation transmission structure was obtained by simulation. From this result, it was confirmed that when the Young's modulus of the material forming the plurality of connection portions is decreased, the bending rigidity decreases. Also, the Young's modulus of the material forming the plurality of connection portions was changed, and the torsional rigidity of the rotation transmission structure was obtained by simulation. From this result, it was confirmed that when the Young's modulus of the material forming the plurality of connection portions is decreased, the torsional rigidity decreases. Furthermore, it was confirmed that when the Young's modulus of the material forming the reinforcing body is gradually decreased, under predetermined conditions, the bending rigidity tends to be smaller than the torsional rigidity. From this result, for example, it was suggested that the bending rigidity and torsional rigidity corresponding to the medical device to which the rotation transmission structure 220 is applied can be realized, such as decreasing the bending rigidity while ensuring the torsional rigidity according to the site of the rotation transmission structure 220.

[0055] The Young's modulus of the material of the connection portion 241 disposed in the first region 21 is smaller than the Young's modulus of the material of the connection portion 242 disposed in the second region 22. Therefore, by changing the Young's modulus of the materials of the connection portions 241 and 242, the rigidity of the rotation transmission structure 220 can be suitably adjusted.

[0056] The plurality of connection portions 241 and 242 are arranged along virtual multi-strand spiral shapes S1 to S4. Therefore, the range of rigidity that can be adjusted by the plurality of connection portions 241 and the plurality of connection portions 242 can be increased as compared with the configuration in which the plurality of connection portions 241 and 242 are arranged along a single spiral shape.

[0057] In this embodiment, since a plurality of connection portions 243 made of materials having different Young's moduli are arranged in the intermediate region 23, the rigidity of the rotation transmission structure 220 can be gradually changed.

[0058] <Embodiment 3> As shown in FIGS. 9 and 10, the rotational transmission structure 320 according to Embodiment 3 has a different configuration of the reinforcing body from that of Embodiment 1. The same components as those in Embodiment 1 are denoted by the same reference numerals, and redundant descriptions are omitted.

[0059] The reinforcing body 340 is composed of a plurality of connecting portions 341 and 342 provided for each portion connecting between the strands 31. Among the plurality of connecting portions 341 and 342, the plurality of connecting portions 341 are arranged in the first region 21, and the plurality of connecting portions 342 are arranged in the second region 22. The plurality of connecting portions 341 and 342 are arranged along a virtual single helical shape S1. This helical shape S1 is opposite to the winding direction of the coil body 30. For example, when the coil body 30 is wound in a counterclockwise direction toward the tip (S winding), the plurality of connecting portions 341 and 342 are arranged along a virtual helical shape S1 that is wound in a clockwise direction toward the tip (Z winding).

[0060] The plurality of connecting portions 341 and 342 are arranged more sparsely in the first region 21 than in the second region 22. In other words, the density of the plurality of connecting portions 341 is smaller than the density of the plurality of connecting portions 342. The density of the plurality of connecting portions 341 can be obtained, for example, as the mass of the plurality of connecting portions 341 per unit length of the coil body 30. The density of the plurality of connecting portions 342 can be obtained in the same manner. At this time, the unit length of the coil body 30 may be appropriately set according to the distribution of the plurality of connecting portions 341 and 342.

[0061] The pitch P1 of the helical shape S1 in the first region 21 is larger than the pitch P2 of the helical shape S1 in the second region 22. The pitch of the helical shape S1 is the dimension between the windings of the helical shape S1 in the length direction of the rotational transmission structure 320. The pitch P1 of the helical shape S1 in the first region 21 is the same throughout the region, and the pitch P2 of the helical shape S1 in the second region 22 is the same throughout the region. That is, the pitch of the helical shape S1 gradually increases toward the tip side.

[0062] In this embodiment, the rigidity of the rotational transmission structure 320 can be suitably adjusted by a simple configuration in which the pitch of the spiral shape is changed step by step. The rotational transmission structure 320 has a rigidity that gradually decreases from the second region 22 toward the first region 21.

[0063] <Embodiment 4> As shown in FIGS. 11 and 12, the rotational transmission structure 420 according to Embodiment 4 differs from Embodiment 1 in the configuration of the reinforcing body. The same reference numerals are given to the same configurations as in Embodiment 1, and redundant descriptions are omitted.

[0064] The reinforcing body 440 is composed of a plurality of connection portions 441 and 442 provided for each portion connecting between the strands 31. Among the plurality of connection portions 441 and 442, the plurality of connection portions 441 are arranged in the first region 21, and the plurality of connection portions 442 are arranged in the second region 22. The plurality of connection portions 441 are arranged along a virtual single spiral shape S1. The plurality of connection portions 442 are arranged along virtual two spiral shapes S1 and S2. These spiral shapes S1 and S2 are opposite to the winding direction of the coil body 30. For example, when the coil body 30 is wound in a counterclockwise direction (S winding) toward the tip, the plurality of connection portions 441 and 442 are arranged along a virtual spiral shape S1 that is wound in a clockwise direction (Z winding) toward the tip. The pitch P1 of the spiral shape S1 is the same as the pitch P2 of the spiral shape S2.

[0065] In this embodiment, the rigidity of the rotational transmission structure 420 can be suitably adjusted by a simple configuration in which the number of strands of the spiral shapes S1 and S2 is changed. The rotational transmission structure 420 has a rigidity that gradually decreases from the second region 22 toward the first region 21.

[0066] <Embodiment 5> The rotational transmission structure 520 according to Embodiment 5 differs from Embodiment 1 in the point of constituting the guide wire 510. The same reference numerals are given to the same configurations as in Embodiment 1, and redundant descriptions are omitted.

[0067] FIG. 13 is an explanatory diagram showing a guide wire (a type of medical device) 510 having a rotation transmission structure 520. The guide wire 510 includes a rotation transmission structure 520 and a core shaft 511 inserted into the lumen of the rotation transmission structure 520. The tip of the rotation transmission structure 520 and the tip of the core shaft 511 are connected by a tip brazed portion 512, and the base end of the rotation transmission structure 520 and the middle portion of the core shaft 511 are connected by a rear end brazed portion 513.

[0068] The rotation transmission structure 520 includes a coil body 30 and a reinforcing body 40. The rotation transmission structure 520 has a first region 21 and a second region 22 located on the base end side of the first region 21. The first region 21 corresponds to a predetermined region in the longitudinal direction. The second region 22 corresponds to other regions. The configuration of the rotation transmission structure 520 is the same as that in the first embodiment, and the description thereof is omitted.

[0069] In the guide wire 510 of this embodiment, the first region 21 in the rotation transmission structure 520 is located on the tip side of the second region 22. Therefore, it is possible to realize a guide wire 510 having excellent rotational transmission performance and ensuring flexibility at the tip portion.

[0070] <Other Embodiments> The present invention is not limited to the embodiments described above and with reference to the drawings. For example, the following embodiments are also included in the technical scope of the present invention.

[0071] (1) In addition to the above embodiments, the positions and ranges of the first region and the second region in the rotation transmission structure can be appropriately changed. For example, the first region is not limited to the tip portion of the shaft portion, and may constitute any region in the shaft portion where flexibility is required. The second region is not limited to the base end side of the first region and may be located on the tip side. The second region is not limited to all regions other than the first region and may constitute a partial region. Further, in addition to the intermediate region, the rotation transmission structure may have a third region having different rigidity from both the first region and the second region.

[0072] (2) The configuration for changing the rigidity of the rotation transmission structure by the reinforcing body is not limited to the configuration of the above embodiment. For example, among the size of the reinforcing body, the physical properties of the material forming the reinforcing body, the pitch of the helical shape, and the number of helical shapes, the rigidity of the rotation transmission structure can be changed by combining and changing one or more of them.

[0073] (3) The reinforcing body is not limited to being composed of a plurality of connecting parts, and may be composed of a single member. In such a case, as shown in FIG. 14, the reinforcing body 640 may be formed in a longitudinal shape with a width dimension decreasing toward the tip side, and portions with different width dimensions of the reinforcing body 640 may be provided in the first region 21 and the second region 22. Further, the reinforcing body 640 composed of such a single member may be provided outside the coil body 30 as shown in FIG. 14, or may be provided inside the coil body.

[0074] (4) The plurality of connecting parts may be arranged along a virtual helical shape in the same direction as the winding direction of the coil body. The plurality of connecting parts do not have to be arranged along the virtual helical shape, and may be arranged, for example, along the longitudinal direction of the coil body.

[0075] (5) In addition to the above embodiment, the configuration of the coil body can be changed. For example, the coil body may have regions with different rigidities in a state where it is not connected by the reinforcing body. The coil body may not have a gap between the wire elements and may be tightly wound. The winding direction of the coil body is not limited.

[0076] (6) In the above embodiment, a configuration in which the diameter of the wire element is substantially constant over the entire length is exemplified, but the diameter of the wire element may become thinner from the base end toward the tip end.

[0077] (7) The mode of change in the rigidity of the rotation transmission structure is not limited to the configuration of the above embodiment. The rigidity of the rotation transmission structure may change gradually or may change stepwise at any number of steps.

[0078] (8) The rotational transmission structure may be provided in a medical device such as a guide wire other than a catheter. The rotational transmission structure may be coated with a resin layer or the like according to the medical device to be used.

Explanation of Signs

[0079] 10 Catheter 11 Shaft portion 11A Tip portion 12 Tip chip 13 Connector 20, 220, 320, 420, 520 Rotational transmission structure 21 First region (predetermined region) 22 Other region (second region) 23 Intermediate region 30 Coil body 31 Strand 32 Gap 34 Outer peripheral surface 34A Virtual cylindrical surface 35 Inner peripheral surface 35A Virtual cylindrical surface 40, 240, 340, 440, 640 Reinforcing body 41, 241, 341, 441 Connection portion (connection portion arranged in a predetermined region) 42, 242, 342, 442 Connection portion (connection portion arranged in other regions) 243 Connection portion 510 Guide wire 511 Core shaft S1, S2, S3, S4 Helical shape

Claims

1. A coil body having a configuration in which a wire is wound; a reinforcing body that connects adjacent wires of the coil body, the reinforcing member is provided such that, in the coil body in a state in which the wires are connected, a predetermined region in a longitudinal direction has a lower rigidity than other regions, The predetermined region is located on a distal side relative to the other region, The reinforcing body is configured by a plurality of connection parts provided at each portion connecting the wires, A rotation transmission structure, characterized in that a size of the plurality of connection portions in the winding direction of the wire is smaller in the specified region than in the other regions.

2. A rotational transmission structure as described in claim 1, characterized in that the size of the multiple connection parts in the winding direction of the wire gradually decreases toward the tip side.

3. A rotational transmission structure as described in claim 1 or claim 2, characterized in that the multiple connection portions are arranged more sparsely in the specified region than in the other regions.

4. The plurality of connection portions are arranged along an imaginary spiral shape, 4. The rotation transmission structure according to claim 3, wherein the pitch of the spiral shape in the predetermined region is larger than the pitch of the spiral shape in the other region.

5. A rotational transmission structure described in any one of claims 1 to 4, characterized in that the Young's modulus of the material of the connection part arranged in the specified region is smaller than the Young's modulus of the material of the connection part arranged in the other region.

6. A rotational transmission structure described in any one of claims 1 to 5, characterized in that the multiple connection portions are arranged along a virtual spiral shape opposite to the winding direction of the coil body.

7. A rotational transmission structure described in any one of claims 1 to 6, characterized in that the multiple connection parts are arranged along a virtual multi-strand spiral shape.

8. 8. The rotation transmission structure according to claim 1, wherein an outer diameter of the reinforcing member is equal to or smaller than a maximum outer diameter of the coil body.

9. A rotational transmission structure described in any one of claims 1 to 8, characterized in that the inner diameter of the reinforcing body is greater than or equal to the minimum inner diameter of the coil body.

10. A catheter comprising a shaft portion reinforced by the rotation transmission structure according to any one of claims 1 to 9.

11. A guidewire comprising: the rotation transmission structure according to claim 1 ; and a core shaft inserted into an inner cavity of the rotation transmission structure.

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