Metal pipes and medical devices

Abstract

This method, which differs from conventional approaches, makes metal pipes less susceptible to plastic deformation, thereby improving the operability of medical devices equipped with metal pipes. [Solution] The medical metal pipe has an uneven surface, and the uneven surface satisfies the following <Condition 1>. <Condition 1> The projected dimensions of the metal pipe are measured using a projection dimension measuring instrument, and the relationship between the outer diameter of the metal pipe and the position in the longitudinal direction of the metal pipe is shown in a graph with the outer diameter of the metal pipe on the vertical axis and the position in the longitudinal direction of the metal pipe on the horizontal axis. The distribution curve shown in this graph satisfies the following <Condition 2>. <Condition 2> The amplitude of the distribution curve is 2 μm or more and 10 μm or less.

Description

Technical Field

[0001] The present disclosure relates to a metal pipe and a medical device.

Background Art

[0002] Medical devices used in percutaneous procedures and including a metal pipe are known. In such medical devices using a metal pipe, it is also known to provide a through-hole that penetrates the inside and outside of the metal pipe in the metal pipe. For example, Patent Document 1 describes a medical instrument including a hypodermic tube with cuts aligned in the circumferential direction to improve flexibility. For example, Patent Document 2 describes a medical instrument including a hypodermic tube with spiral cuts on the surface. For example, Patent Document 3 describes that in a guide wire including a metal tubular member, a slot extending between the inner circumferential surface and the outer circumferential surface is provided in the tubular member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present disclosure is to provide a metal pipe having excellent resilience.

Means for Solving the Problems

[0005] The present disclosure has been made to solve the above problems and can be realized in the following forms.

[0006] According to one embodiment of the present disclosure, a medical metal pipe is provided. The metal pipe has an uneven surface, and the uneven surface satisfies the following condition 1. <Condition 1> The projected dimensions of the metal pipe are measured using a projection dimension measuring instrument, and the relationship between the outer diameter of the metal pipe and the position of the metal pipe in the longitudinal direction is expressed in a graph with the outer diameter of the metal pipe on the vertical axis and the position of the metal pipe in the longitudinal direction on the horizontal axis, and the distribution curve expressed in the graph satisfies the following condition 2. <Condition 2> The amplitude of the distribution curve is 2 μm or more and 10 μm or less. [Brief explanation of the drawing]

[0007] [Figure 1] This is an external view of a metal pipe. [Figure 2] Figure 1 is a longitudinal cross-sectional view of the metal pipe shown. [Figure 3] This graph shows the measurement results of the uneven surface shape of a metal pipe. [Figure 4] This is an explanatory diagram of the test method for restorative properties. [Figure 5] This is an explanatory diagram of the method for measuring residual angle. [Figure 6] This is a table showing the test results regarding resilience. [Figure 7] This is an explanatory diagram of the test method for rotational tracking performance. [Figure 8] This graph shows the test results regarding rotational tracking performance. [Figure 9] This is an external view of the metal pipe according to the second embodiment. [Figure 10] This is an external view of the metal pipe according to the third embodiment. [Figure 11] This is an external view of the metal pipe according to the fourth embodiment. [Figure 12] This is a longitudinal cross-sectional view of the metal pipe according to the fifth embodiment. [Modes for carrying out the invention]

[0008] <First Embodiment> Figure 1 is an external view of the metal pipe 1. Figure 2 is a longitudinal cross-sectional view of the metal pipe 1 shown in Figure 1. The metal pipe 1 is for medical use. The metal pipe 1 can be used as one of the components that form a medical device used in percutaneous procedures. Medical devices refer to, for example, guide wires and catheters. In other words, the metal pipe 1 is inserted into the luminal cavity of a living body, such as the vascular system, lymphatic system, biliary system, urinary tract system, respiratory system, digestive system, secretory glands and reproductive organs.

[0009] Figure 1 includes some parts where the relative sizes of each component differ from reality, for the sake of explanation. Figure 1 also includes parts where the metal pipe 1 is exaggerated. Figure 1 illustrates mutually orthogonal XYZ axes. The X-axis corresponds to the longitudinal direction of the metal pipe 1 and each component. The X-axis corresponds to the axial direction of the metal pipe 1. The Y-axis corresponds to the height direction of the metal pipe 1 and each component. The Z-axis corresponds to the width direction of the metal pipe 1 and each component. The direction along the -X axis is called the "tip side" of the metal pipe 1 and each component. The direction along the +X axis is called the "proximal end side" of the metal pipe 1 and each component. Hereafter, of the two ends of the metal pipe 1 and each component in the longitudinal direction, the end located on the tip side will be called the "tip," and the other end located on the proximal end side will be called the "proximal end." The tip and its vicinity will be called the "tip portion," and the proximal end and its vicinity will be called the "proximal end portion." The tip side is inserted into the body, and the proximal end side is manipulated by a surgeon such as a physician. These points are also common in Figure 2 and beyond. In this embodiment, "same" and "equal" mean being approximately the same, and allow for variations due to manufacturing errors, etc. In this embodiment, "constant" also includes being approximately constant, and allow for variations due to manufacturing errors, etc.

[0010] The metal pipe 1 has an uneven surface. The metal pipe 1 has n large diameter sections and m small diameter sections. n can be any natural number. m can be a natural number between n-1 and n+1. The uneven surface of the metal pipe 1 is formed by these n large diameter sections and m small diameter sections. The large diameter sections are parts of the metal pipe 1 where the outer diameter of the metal pipe 1 is relatively large. The small diameter sections are parts of the metal pipe 1 where the outer diameter of the metal pipe 1 is relatively small. The large diameter sections and small diameter sections are arranged alternately in the longitudinal direction of the metal pipe 1. The large diameter sections and small diameter sections are arranged alternately in the X-axis direction. In Figure 1, the height of the metal pipe 1 in the Y-axis direction is called the "outer diameter". In this respect, the explanation remains the same even if the width of the metal pipe 1 in the Z-axis direction is called the "outer diameter". In other words, the metal pipe 1 shown in Figure 1 retains the same uneven surface shape as in Figure 1 even when rotated 90 degrees in the circumferential direction. Furthermore, the metal pipe 1 shown in Figure 1 retains the same uneven surface shape as in Figure 1 even when rotated by any angle in the circumferential direction.

[0011] In the examples shown in Figures 1 and 2, the metal pipe 1 has three large-diameter sections and three small-diameter sections. Specifically, the metal pipe 1 in Figures 1 and 2 has, from the tip end to the base end, a first large-diameter section 11, a first small-diameter section 12, a second large-diameter section 21, a second small-diameter section 22, a third large-diameter section 31, and a third small-diameter section 32.

[0012] The first large-diameter section 11 is a portion of the metal pipe 1 enclosed by a dashed rectangle. The first large-diameter section 11 is located at the very tip of the metal pipe 1 and is a portion of the metal pipe 1 with a relatively large outer diameter. The outer diameter Φ11 of the first large-diameter section 11 gradually increases from both ends toward the center. The inner diameter Φ110 of the first large-diameter section 11 gradually increases from both ends toward the center. The longitudinal length L11 of the first large-diameter section 11 can be determined arbitrarily.

[0013] The first reduced-diameter portion 12 is a part of the metal pipe 1 enclosed by a dashed rectangle. The first reduced-diameter portion 12 is a part of the metal pipe 1 that is located on the proximal end side of the first large-diameter portion 11 and has a relatively small outer diameter of the metal pipe 1. The outer diameter Φ12 of the first reduced-diameter portion 12 gradually decreases from both ends of the first reduced-diameter portion 12 toward the central portion. The inner diameter Φ120 of the first reduced-diameter portion 12 gradually decreases from both ends of the first reduced-diameter portion 12 toward the central portion. The length L12 of the first reduced-diameter portion 12 in the longitudinal direction can be arbitrarily determined.

[0014] The second large-diameter portion 21 is a part of the metal pipe 1 that is located on the proximal end side of the first reduced-diameter portion 12 and has a relatively large outer diameter of the metal pipe 1. The outer diameter Φ21 of the second large-diameter portion 21 gradually increases from both ends of the second large-diameter portion 21 toward the central portion. The inner diameter Φ210 of the second large-diameter portion 21 gradually increases from both ends of the second large-diameter portion 21 toward the central portion. The length L21 of the second large-diameter portion 21 in the longitudinal direction can be arbitrarily determined.

[0015] The second reduced-diameter portion 22 is a part of the metal pipe 1 that is located on the proximal end side of the second large-diameter portion 21 and has a relatively small outer diameter of the metal pipe 1. The outer diameter Φ22 of the second reduced-diameter portion 22 gradually decreases from both ends of the second reduced-diameter portion 22 toward the central portion. The inner diameter Φ220 of the second reduced-diameter portion 22 gradually decreases from both ends of the second reduced-diameter portion 22 toward the central portion. The length L22 of the second reduced-diameter portion 22 in the longitudinal direction can be arbitrarily determined.

[0016] The third large-diameter portion 31 is a part of the metal pipe 1 that is located on the proximal end side of the second reduced-diameter portion 22 and has a relatively large outer diameter of the metal pipe 1. The outer diameter Φ31 of the third large-diameter portion 31 gradually increases from both ends of the third large-diameter portion 31 toward the central portion. The inner diameter Φ310 of the third large-diameter portion 31 gradually increases from both ends of the third large-diameter portion 31 toward the central portion. The length L31 of the third large-diameter portion 31 in the longitudinal direction can be arbitrarily determined.

[0017] The third narrow-diameter section 32 is a portion of the metal pipe 1 located closer to the base end than the third wide-diameter section 31, with a relatively smaller outer diameter. The outer diameter Φ32 of the third narrow-diameter section 32 gradually decreases from both ends toward the center. The inner diameter Φ320 of the third narrow-diameter section 32 also gradually decreases from both ends toward the center. The longitudinal length L32 of the third narrow-diameter section 32 can be determined arbitrarily.

[0018] In the illustrated example, the length L11 of the first large diameter section 11 is the same as the length L12 of the first small diameter section 12. Lengths L11 and L12 may be different. The length L11 of the first large diameter section 11 is the same as the length L21 of the second large diameter section 21 and the length L31 of the third large diameter section 31, respectively. At least a portion of lengths L11, L21, and L31 may be different. The length L12 of the first small diameter section 12 is the same as the length L22 of the second small diameter section 22. The length L12 of the first small diameter section 12 is longer than the length L32 of the third small diameter section 32. Lengths L12, L22, and L32 may be the same, respectively. At least a portion of lengths L12, L22, and L32 may be different.

[0019] In the illustrated example, the maximum value of the outer diameter Φ11 of the first large diameter section 11 is the same as the maximum value of the outer diameter Φ21 of the second large diameter section 21 and the maximum value of the outer diameter Φ31 of the third large diameter section 31. For example, the maximum value of the outer diameter Φ11 of the first large diameter section 11 can be 0.1 mm or more and 5.0 mm or less. At least some of the maximum values ​​of the outer diameters Φ11, Φ21, and Φ31 may differ. The minimum value of the outer diameter Φ12 of the first small diameter section 12 is the same as the minimum value of the outer diameter Φ22 of the second small diameter section 22 and the minimum value of the outer diameter Φ32 of the third small diameter section 32. At least some of the minimum values ​​of the outer diameters Φ12, Φ22, and Φ32 may differ.

[0020] As shown in Figure 2, the metal pipe 1 has a certain thickness T1. Thickness T1 is the wall thickness of the metal pipe 1. Thickness T1 is 10 μm or more and 200 μm or less. The metal pipe 1 in this embodiment is made of metal. The metal pipe 1 in this embodiment is made of stainless steel. Examples of stainless steel include SUS302, SUS304, SUS316, etc. The metal pipe 1 is made of stainless steel.

[0021] Figure 3 is a graph showing the measurement results of the uneven surface shape of the metal pipe 1. The worker measured the dimensions of the uneven surface shape of the outer surface of the metal pipe 1 shown in Figures 1 and 2. Specifically, the worker used a projection dimension measuring instrument to measure the projected dimensions of the metal pipe 1 as viewed from a direction perpendicular to the longitudinal direction of the metal pipe 1, along the entire length of the metal pipe 1. The direction perpendicular to the longitudinal direction can be, for example, the Z-axis direction. The projection dimension measuring instrument used was the LS-7010 high-speed, high-precision digital dimension measuring instrument manufactured by Keyence Corporation. The projection dimension measuring instrument has a light-emitting unit and a light-receiving unit arranged opposite each other, and is a device that measures the outer diameter of an object to be measured placed between the light-emitting unit and the light-receiving unit. The light-emitting unit irradiates parallel light toward the light-receiving unit. The light-receiving unit measures the outer diameter of the object to be measured by detecting the edge position of the brightness and darkness of the light received by the light-receiving element or CCD. The operator placed the metal pipe 1 between the light-emitting and light-receiving parts of the projection dimension measuring device, and performed the measurement while moving the portion of the metal pipe 1 that receives light from the light-emitting part from the tip to the base over time. The operator may also measure the projection dimension of only a portion of the metal pipe 1.

[0022] Next, the operator obtained the distribution curve of projected dimensions output from the projection dimension measuring instrument. An example of the obtained distribution curve DC is shown in Figure 3. The distribution curve DC represents the relationship between the outer diameter of the metal pipe 1 and the position of the metal pipe 1 in the longitudinal direction. The distribution curve DC is represented on the graph in Figure 3, with the outer diameter of the metal pipe 1 on the vertical axis and the position of the metal pipe 1 in the longitudinal direction on the horizontal axis. The length [mm] on the horizontal axis corresponds to the transition of the position of the metal pipe 1 in the longitudinal direction. That is, the tip of the metal pipe 1 corresponds to a length of 0 mm, and the base of the metal pipe 1 corresponds to a length of 900 mm.

[0023] As shown in Figure 3, the distribution curve DC has a first peak DC11, a first valley DC12, a second peak DC21, a second valley DC22, a third peak DC31, and a third valley DC32, arranged from smallest to largest length [mm] values. The first peak DC11, the second peak DC21, and the third peak DC31 are the parts where the detected outer diameter values ​​form peaks. The first peak DC11, the second peak DC21, and the third peak DC31 are collectively referred to as "peaks." The first valley DC12, the second valley DC22, and the third valley DC32 are the parts where the detected outer diameter values ​​form valleys. The first valley DC12, the second valley DC22, and the third valley DC32 are collectively referred to as "valleys." The reason the distribution curve DC has a zigzag shape rather than a smooth curve is due to the detection of fine irregularities present on the outer surface of the metal pipe 1. The fine irregularities present on the outer surface of the metal pipe 1 are a result of the manufacturing process and are unrelated to the shape of the metal pipe 1's irregularities.

[0024] The first peak DC11 of the distribution curve DC corresponds to the first wide-diameter section 11. In other words, the first peak DC11 represents the detected value of the first wide-diameter section 11. The maximum detected outer diameter within the first peak DC11 is equal to the outer diameter Φ11 of the metal pipe 1. The first trough DC12 of the distribution curve DC corresponds to the first narrow-diameter section 12. In other words, the first trough DC12 represents the detected value of the first narrow-diameter section 12. The minimum detected outer diameter within the first trough DC12 is equal to the outer diameter Φ12 of the metal pipe 1.

[0025] The second peak DC21 of the distribution curve DC corresponds to the second wide-diameter section 21. In other words, the second peak DC21 represents the detected value of the second wide-diameter section 21. The maximum detected outer diameter within the second peak DC21 is equal to the outer diameter Φ21 of the metal pipe 1. The second valley DC22 of the distribution curve DC corresponds to the second narrow-diameter section 22. In other words, the second valley DC22 represents the detected value of the second narrow-diameter section 22. The minimum detected outer diameter within the second valley DC22 is equal to the outer diameter Φ22 of the metal pipe 1.

[0026] The third peak DC31 of the distribution curve DC corresponds to the third wide-diameter section 31. In other words, the third peak DC31 represents the detected value of the third wide-diameter section 31. The maximum detected outer diameter within the third peak DC31 is equal to the outer diameter Φ31 of the metal pipe 1. The third valley DC32 of the distribution curve DC corresponds to the third narrow-diameter section 32. In other words, the third valley DC32 represents the detected value of the third narrow-diameter section 32. The minimum detected outer diameter within the third valley DC32 is equal to the outer diameter Φ32 of the metal pipe 1.

[0027] In other words, in the distribution curve DC shown in the graph in Figure 3, peaks corresponding to the wide-diameter portion and troughs corresponding to the narrow-diameter portion alternately repeat along the horizontal axis of the graph.

[0028] The wavelength λ of the distribution curve DC is the distance from one trough to the next. "The first trough" and "the next trough" refer to the point within the trough section where the detected outer diameter value is smallest. In the example in Figure 3, the wavelength λ is the distance between the point in the first trough DC12 where the detected outer diameter value is smallest and the point in the second trough DC22 where the detected outer diameter value is smallest. The amplitude A of the distribution curve DC is the distance from one peak to the troughs continuous with that peak. "One peak" refers to the point within the peak section where the detected outer diameter value is largeest. In the example in Figure 3, the amplitude A is the distance between the point in the first peak DC11 where the detected outer diameter value is largeest and the point in the first trough DC12 where the detected outer diameter value is smallest.

[0029] In the metal pipe 1 of this embodiment, the distribution curve DC obtained by the method described above satisfies the following condition 2. As described above, the distribution curve DC obtained from the metal pipe 1 has multiple peaks caused by multiple large diameter sections and multiple valleys caused by multiple small diameter sections. Condition 2 only needs to be satisfied by any one pair of peaks and valleys. <Condition 2> The amplitude A of the distribution curve DC is 2 μm or more and 10 μm or less. Alternatively, the amplitude A of the distribution curve DC may be 2 μm or more and 5 μm or less.

[0030] If the distribution curve DC does not satisfy condition 2, regardless of the magnitude of the amplitude A, the residual angle θ, described later, becomes larger, resulting in a metal pipe with poor resilience.

[0031] The metal pipe 1 described above can be manufactured, for example, as follows: The worker prepares a normal metal pipe that does not have an uneven surface. This metal pipe can be a commercially available product made of stainless steel. Hereafter, this metal pipe will be referred to as the "raw material pipe". The worker forms an uneven surface on the raw material pipe by applying a swaging process. Alternatively, the worker may form an uneven surface on the raw material pipe by applying a centerless grinding process instead of swaging.

[0032] Figure 4 is an explanatory diagram of the test method for restorability. The operator performed the test for restorability using the test apparatus 70 shown in Figure 4. The test apparatus 70 is a simulated path that simulates a biological lumen into which the metal pipe 1 is inserted. The test apparatus 70 is a plate-shaped member with a groove 71. The groove 71 is a U-shaped recess formed on one surface of the plate-shaped member. The radius Φ71 of the groove 71 is 30 mm. As shown in the upper part of Figure 4, the operator inserted the sample S into the groove 71 from one end. The operator performed a back-and-forth motion of the sample S using the groove 71. Specifically, as shown in the middle part of Figure 4, the operator pushed the sample S forward until the tip Sb of the sample S was housed inside the groove 71. Next, as shown in the lower part of Figure 4, the operator pushed the sample S in the reverse direction until the base Sa of the sample S was housed inside the groove 71. After that, the operator removed the sample S and measured the residual angle of the sample S.

[0033] Figure 5 is an explanatory diagram of the method for measuring the residual angle. The worker placed the removed sample S on the workbench and determined the angle θ that is outside the sample S, which is the angle formed by the virtual extension line VL1, which is the extension of the straight portion of the base end Sa, and the virtual extension line VL2, which is the extension of the straight portion of the tip end Sb. The angle θ is the residual angle of the sample S. The worker performed the procedure described in Figures 4 and 5 on both samples S1 to S5 of the metal pipe 1 described above, and on sample S6, which is different from the metal pipe 1 described above. Sample S6 is a metal pipe that does not have an uneven shape on its outer surface.

[0034] Figure 6 is a table of test results regarding resilience. In this embodiment, test result S1 showed a residual angle of 21°. Test result S2 showed a residual angle of 22°. Test result S3 showed a residual angle of 24°. Test result S4 showed a residual angle of 26°. Test result S5 showed a residual angle of 25°. As a comparative example, test result S6 showed a residual angle of 34.5°. From the above, the metal pipe 1 having an uneven surface has a smaller residual angle compared to the metal pipe without an uneven surface. In other words, the metal pipe 1 having an uneven surface has superior resilience compared to the metal pipe without an uneven surface.

[0035] Figure 7 is an explanatory diagram of the test method for rotational followability. The operator performed the rotational followability test using the tube 80 shown in Figure 7. The tube 80 is a simulated path that simulates a biological lumen into which the metal pipe 1 is inserted. The tube 80 has a straight section 81 and a loop section 82. The loop section 82 is located near the center of the tube 80 and is the part of the tube that is curved in an annular shape. The radius Φ82 of the loop section 82 is 30 mm. The straight section 81 is located at both ends of the loop section 82 and is the part of the tube that extends in a straight line. An opening for inserting a sample into the tube is formed at the end of the straight section 81. The operator inserted the sample S into the tube 80 from one of the openings of the tube 80. The operator pushed the sample S toward the tip and, as shown in Figure 7, the tip Sb of the sample S protruded from the other opening of the tube 80. The worker grasped the base end Sa of sample S in the state shown in Figure 7 and rotated sample S, measuring the rotation angle of the base end Sa and the rotation angle of the tip end Sb of sample S. The worker performed the procedure described in Figure 7 on both sample S2 of the metal pipe 1 described above and sample S6, which is different from the metal pipe 1 described above. Sample S6 is a metal pipe that does not have an uneven surface.

[0036] Figure 8 is a graph showing the test results regarding rotational tracking performance. The input [°] shown on the horizontal axis is the rotation angle of the base end Sa of sample S. The output [°] shown on the vertical axis is the rotation angle of the tip end Sb of sample S. The graph in Figure 8 illustrates the ideal straight IC, the test result S2 of sample S2, and the test result S6 of sample S6. In the ideal straight IC, the rotation of the tip end Sb perfectly follows the rotation of the base end Sa, making it ideal in terms of rotational tracking performance. The test result S2 of this embodiment shows that, compared to the ideal straight IC, the output lags slightly behind the input, but it is generally close to the ideal straight IC and can be seen to have excellent rotational tracking performance. In the comparative example test result S6, there are two places where the output lags significantly behind the input. Since the shape of test result S6 is not close to a straight line but curved, it can be seen that a bounce occurs at the tip end Sb when the base end Sa rotates. Therefore, it can be seen that the comparative example test result S6 has inferior rotational tracking performance. Based on the above, it can be said that metal pipe 1, which has an uneven surface on its outer surface, exhibits superior rotational followability even in environments where bending deformation is applied, compared to metal pipes that do not have an uneven surface on their outer surface.

[0037] As described above, the uneven shape formed on the outer surface of the metal pipe 1 of the first embodiment satisfies condition 2 when represented by a distribution curve DC on a graph with the outer diameter on the vertical axis and the position in the longitudinal direction on the horizontal axis. <Condition 2> The amplitude A of the distribution curve DC is 2 μm or more and 10 μm or less. Therefore, when bending deformation is applied to the metal pipe 1, the stress on the surface of the metal pipe 1 is distributed, making it less likely for the metal pipe 1 to undergo plastic deformation. As a result, as explained in Figures 4 to 6, the resilience of the metal pipe 1 when bending deformation is applied can be improved. Furthermore, as explained in Figures 7 and 8, the rotational followability of the metal pipe 1 in an environment where bending deformation is applied can be improved. The uneven shape of the metal pipe 1 is different from the through holes that penetrate the inside and outside of the metal pipe 1. That is, the uneven shape of the metal pipe 1 is brought about by the existence of relatively raised parts and relatively recessed parts on the outer surface of the metal pipe 1. The relatively raised parts are the larger diameter parts. The relatively recessed parts are the smaller diameter parts. Therefore, according to the metal pipe 1 of the first embodiment, it is possible to make the metal pipe 1 less likely to undergo plastic deformation in a different way than conventional methods, and to improve the operability of medical devices equipped with the metal pipe 1.

[0038] Furthermore, in the metal pipe 1 of the first embodiment, the distribution curve DC obtained by the method described above satisfies the following condition 3 in addition to condition 2. Condition 3 only needs to be satisfied by any one pair of valleys in the metal pipe 1. <Condition 3> The wavelength λ of the distribution curve DC is 50 mm or more and 1000 mm or less. If the distribution curve DC does not satisfy condition 3 and the wavelength λ is less than 50 mm, the residual angle θ, described later, will be large, which may result in a metal pipe with poor resilience. If the distribution curve DC does not satisfy condition 3 and the wavelength λ exceeds 1000 mm, the stress distribution effect on the surface of the metal pipe will not be obtained, which may result in a metal pipe that is prone to plastic deformation.

[0039] Furthermore, the wall thickness of the metal pipe 1 in the first embodiment is 10 μm or more and 200 μm or less. Therefore, according to the above embodiment, a metal pipe 1 with excellent resilience and rotational tracking ability can be provided.

[0040] Furthermore, the wall thickness of the metal pipe 1 in the first embodiment is constant throughout, from the tip to the base. Therefore, a metal pipe 1 having an uneven surface can be manufactured by processing a normal metal pipe that does not have an uneven surface.

[0041] Furthermore, the metal pipe 1 in the first embodiment is made of stainless steel. Therefore, compared to the case where the metal pipe is made of a superelastic alloy such as nickel-titanium, the torque transmission performance of the metal pipe 1 can be improved.

[0042] <Second Embodiment> Figure 9 is an external view of the metal pipe 1A of the second embodiment. The metal pipe 1A of the second embodiment is provided with a first small diameter portion 12A in place of the first small diameter portion 12, a second large diameter portion 21A in place of the second large diameter portion 21, and a second small diameter portion 22A in place of the second small diameter portion 22, as described in the embodiment of the first embodiment. The only difference between the first small diameter portion 12A, the second large diameter portion 21A, and the second small diameter portion 22A and the first small diameter portion 12A is their length L12A, L21A, and L22A in the longitudinal direction of the metal pipe 1A, compared to the first embodiment.

[0043] The longitudinal length L21A of the second large diameter portion 21A is longer than the longitudinal length L11 of the first large diameter portion 11 and longer than the longitudinal length L31 of the third large diameter portion 31. The longitudinal length L21A of the second large diameter portion 21A is longer than the longitudinal length L12A of the first small diameter portion 12A and longer than the longitudinal length L22A of the second small diameter portion 22A. In the illustrated example, the longitudinal length L12A of the first small diameter portion 12A and the longitudinal length L22A of the second small diameter portion 22A are the same. Lengths L12A and L22A may be different from each other.

[0044] Thus, in the metal pipe 1A, the lengths of the large diameter section and the small diameter section are not uniform and may vary. When the distribution curve DC described in Figure 3 is obtained for the metal pipe 1A, the wavelength λ between the first small diameter section 12A and the second small diameter section 22A is also called λa. The wavelength λ between the second small diameter section 22A and the third small diameter section 32 is also called λb. In the metal pipe 1A, the wavelength λa is greater than the wavelength λb. In the metal pipe 1A, it is preferable that at least one of the wavelengths λa and λb satisfies <Condition 3>. In the example in Figure 9, the wavelength λ in the central part of the distribution curve DC of the metal pipe 1A is made relatively longer. In the distribution curve DC of the metal pipe 1A, the wavelength λ at the base end may be relatively longer than that at the tip end. In the metal pipe 1A, the wavelength λ may gradually increase from the tip end to the base end. The same effects as in the first embodiment can be achieved in such a second embodiment of the metal pipe 1A.

[0045] <Third Embodiment> Figure 10 is an external view of the metal pipe 1B of the third embodiment. The metal pipe 1B of the third embodiment is provided with a second large diameter portion 21B in place of the second large diameter portion 21 as described in the first embodiment. The only difference of the second large diameter portion 21B from the first embodiment is its outer diameter Φ21B. The outer diameter Φ21B of the second large diameter portion 21B is larger than the outer diameter Φ11 of the first large diameter portion 11 and larger than the outer diameter Φ31 of the third large diameter portion 31. The outer diameters Φ11 and Φ31 may be different from each other.

[0046] Thus, in the metal pipe 1B, the outer diameter of the large diameter section is not uniform and may vary. Similarly, the outer diameter of the small diameter section is not uniform and may vary. When the distribution curve DC described in Figure 3 is obtained for the metal pipe 1B, the amplitude A between the first large diameter section 11 and the first small diameter section 12 is also called Aa. The amplitude A between the second large diameter section 21B and the second small diameter section 22 is also called Ab. The amplitude A between the third large diameter section 31 and the third small diameter section 32 is also called Ac. In the metal pipe 1B, amplitude Ab is greater than amplitude Aa and greater than amplitude Ac. In the metal pipe 1B, it is sufficient that at least one of amplitudes Aa, Ab, and Ac satisfies <Condition 2>. The same effects as in the first embodiment can be achieved in this third embodiment of the metal pipe 1B.

[0047] <Fourth Embodiment> Figure 11 is an external view of the metal pipe 1C of the fourth embodiment. In the embodiment described in the first embodiment, the metal pipe 1C has a straight section 50 instead of the third large-diameter section 31 and the third small-diameter section 32.

[0048] The straight section 50 is located closer to the base end than the second narrow-diameter section 22. The straight section 50 is a part of the metal pipe 1C, and is a portion of the metal pipe 1C with a constant outer diameter. No uneven surface is formed on the outer surface of the straight section 50. Uneven surface is different from the fine irregularities that occur during the manufacturing of the metal pipe. The outer diameter Φ50 of the straight section 50 is the same as the outer diameter Φ11 of the first wide-diameter section 11 and the outer diameter Φ21 of the second wide-diameter section 21. The outer diameter Φ50 can be determined arbitrarily. For example, the outer diameter Φ50 may be the same as the outer diameter Φ12 of the first narrow-diameter section 12. For example, the outer diameter Φ50 may be different from the outer diameters Φ11 and Φ12.

[0049] Thus, the metal pipe 1C may include a straight section 50 in a portion of its longitudinal direction. In the example shown in Figure 11, the straight section 50 is provided at the base end of the metal pipe 1C. The straight section 50 may also be provided at the tip of the metal pipe 1C. The straight section 50 may also be provided in the middle of the uneven shape of the metal pipe 1C. The middle of the uneven shape can be, for example, between the first small diameter section 12 and the second large diameter section 21. In this fourth embodiment of the metal pipe 1C, the same effects as in the first embodiment can be achieved by the uneven shape of the portion excluding the straight section 50.

[0050] <Fifth Embodiment> Figure 12 is a longitudinal cross-sectional view of the metal pipe 1D of the fifth embodiment. The metal pipe 1D of the fifth embodiment has non-uniform thicknesses T11 to T32, as described in the embodiment of the first embodiment. Unlike the metal pipe 1 described in the first embodiment, the inner diameter Φ1 of the metal pipe 1D is constant.

[0051] The thickness T11 in the first large diameter section 11 gradually increases from both ends toward the center of the first large diameter section 11. The thickness T12 in the first small diameter section 12 gradually decreases from both ends toward the center of the first small diameter section 12. The thickness T21 in the second large diameter section 21 gradually increases from both ends toward the center of the second large diameter section 21. The thickness T22 in the second small diameter section 22 gradually decreases from both ends toward the center of the second small diameter section 22. The thickness T31 in the third large diameter section 31 gradually increases from both ends toward the center of the third large diameter section 31. The thickness T32 in the third small diameter section 32 gradually decreases from both ends toward the center of the third small diameter section 32. The maximum values ​​of thicknesses T11, T21, and T31 are the same. The minimum values ​​of thicknesses T12, T22, and T32 are the same. At least one of the thicknesses T11 to T32 may be less than 10 μm. At least one of the thicknesses T11 to T32 may be greater than 200 μm.

[0052] Thus, the thickness of the metal pipe 1D may be non-uniform. Thicknesses T11 to T32 may differ from each other. In this fifth embodiment of the metal pipe 1D, the same effects as in the first embodiment can be achieved by the uneven shape of the outer surface of the metal pipe 1D. Furthermore, according to the fifth embodiment of the metal pipe 1D, the inner diameter Φ1 can be kept constant. For this reason, the metal pipe 1D can be made suitable for medical devices in which a liquid medicine is flowed into the lumen of the metal pipe 1D.

[0053] <Modified form of this embodiment> This disclosure is not limited to the embodiments described above, and can be implemented in various forms without departing from its essence, including, for example, the following modifications.

[0054] [Example 1] The first to fifth embodiments described above show examples of metal pipes 1, 1A to 1D. The configurations of metal pipes 1, 1A to 1D can be modified in various ways. For example, a worker may combine metal pipe 1 with other components to form medical devices such as pressure guide wires, sensor guide wires, catheters, and needle catheters. The metal pipe 1 in this embodiment may be used as a hypotube, which is a small-diameter tube used in medical devices.

[0055] In the above embodiment, the uneven shape of the outer surface of the metal pipe 1 is assumed to change smoothly. However, the uneven shape of the outer surface of the metal pipe 1 does not have to change smoothly. In other words, there may be a step at the boundary between the large diameter portion and the small diameter portion on the outer surface of the metal pipe 1.

[0056] In the above embodiment, the outer surface of the metal pipe 1 is raised by a uniform length in the circumferential direction in the larger diameter portion. The outer surface of the metal pipe 1 may be raised by an uneven length in the circumferential direction in the larger diameter portion. In the metal pipe 1 is recessed by a uniform length in the circumferential direction in the smaller diameter portion. The outer surface of the metal pipe 1 may be recessed by an uneven length in the circumferential direction in the smaller diameter portion.

[0057] In the above embodiment, the metal pipe 1 is made of stainless steel. The metal pipe 1 may have different metallic properties than stainless steel. For example, the metal pipe 1 may be made of a superelastic alloy such as nickel-titanium, or of an X-ray opaque material such as platinum, gold, palladium, tungsten, rhenium, or alloys containing these metallic elements. For example, the metal pipe 1 may be formed of a cobalt-based alloy such as a cobalt-chromium alloy, a nickel-chromium alloy, or the like.

[0058] [Differentiation 2] The metal pipes 1, 1A to 1D of the first to fifth embodiments described above, and the metal pipes 1, 1A to 1D of the modified example 1 described above, may be combined as appropriate. For example, a metal pipe 1 may be formed that has any two or more of the following characteristics: a different wavelength λ of the distribution curve DC described in the second embodiment, a different amplitude A of the distribution curve DC described in the third embodiment, a straight section 50 described in the fourth embodiment, and a non-uniform thickness described in the fifth embodiment.

[0059] This embodiment has been described above based on embodiments and modifications. The embodiments described above are for the purpose of facilitating understanding of this embodiment and do not limit it. This embodiment can be modified and improved without departing from its spirit and the scope of the claims, and equivalents thereof are included in this embodiment. Technical features that are not described as essential in this specification may be deleted as appropriate.

Claims

1. Medical metal pipes (1, 1A to 1D), It has an uneven surface, The aforementioned uneven shape is a metal pipe (1, 1A to 1D) that satisfies the following condition 1. <Condition 1> Using a projection dimension measuring instrument, the projection dimensions of the metal pipes (1, 1A to 1D) as viewed from a direction perpendicular to the longitudinal direction of the metal pipes (1, 1A to 1D) are measured. Of the obtained projection dimensions, the distribution curve (DC) representing the relationship between the outer diameter of the metal pipes (1, 1A to 1D) and the position of the metal pipes (1, 1A to 1D) in the longitudinal direction, with the outer diameter of the metal pipes (1, 1A to 1D) on the vertical axis and the position of the metal pipes (1, 1A to 1D) on the horizontal axis, satisfies the following <Condition 2>. <Condition 2> The amplitude (A) of the distribution curve (DC) is 2 μm or more and 10 μm or less.

2. A metal pipe (1,1A to 1D) according to claim 1, The aforementioned metal pipes (1, 1A to 1D) include: The metal pipe (1, 1A to 1D) has a relatively large outer diameter in the large-diameter section (11, 21, 21A, 21B, 31), The metal pipes (1, 1A to 1D) have relatively small outer diameter sections (12, 12A, 22, 22A, 32) and are arranged alternately in the longitudinal direction of the metal pipes (1, 1A to 1D). In the aforementioned graph, The top portions (DC11, DC21, DC31) corresponding to the large diameter portions (11, 21, 21A, 21B, 31), The valleys (DC12, DC22, DC32) corresponding to the narrow diameter sections (12, 12A, 22, 22A, 32) are alternately repeated on the horizontal axis of the graph. The wavelength (λ) of the distribution curve (DC) is the distance from one trough (DC12) to the next trough (DC22). The amplitude (A) of the distribution curve (DC) is the distance from one peak (DC11) to the valley (DC12) that is continuous with the peak (DC11), in a metal pipe (1, 1A to 1D).

3. A metal pipe (1, 1A to 1C) according to claim 1 or claim 2, The metal pipes (1, 1A to 1C) have a wall thickness (T1) of 10 μm or more and 200 μm or less.

4. A metal pipe (1,1A to 1C) according to claim 3, The wall thickness (T1) is constant throughout the entire length of the metal pipe (1, 1A to 1C) from the tip to the base end.

5. A metal pipe (1,1A to 1D) according to any one of claims 1 to 4, The aforementioned metal pipes (1, 1A to 1D) are made of stainless steel.

6. A metal pipe (1,1A to 1D) according to any one of claims 1 to 5, The above-mentioned condition 1 for the uneven shape is a metal pipe (1, 1A to 1D) that satisfies the following condition 3 in addition to the above-mentioned condition 2. <Condition 3> The wavelength (λ) of the distribution curve (DC) is 50 mm or more and 1000 mm or less.

7. A medical device comprising a metal pipe (1, 1A to 1D) according to any one of claims 1 to 6.

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