Bending apparatus and wire manufacturing method

Abstract

The present invention provides a bending device that can smoothly bend extremely thin and delicate wires, such as extension resistance members, into a wavy shape without damaging them. [Solution] A bending apparatus for a wire 4 having a first gear 1 having a first group of teeth 1t and a second gear 2 having a second group of teeth 2t that rotates synchronously with the first gear 1, wherein when the first gear 1 and the second gear 2 are rotated with the wire 4 positioned between the first group of teeth 1t and the second group of teeth 2t, the wire 4 is bent by contacting the first group of teeth 1t and the second group of teeth 2t, and when the first gear 1 and the second gear 2 are rotated with the wire 4 not positioned between the first group of teeth 1t and the second group of teeth 2t, the first group of teeth 1t and the second group of teeth 2t do not come into contact with each other.

Description

Technical Field

[0001] The present invention relates to a bending apparatus suitable for bending extremely thin wires, such as an elongation resistance member disposed in the lumen of a coil forming an in-vivo indwelling device, and a method for manufacturing the wire.

Background Art

[0002] An in-vivo indwelling device suitable for endovascular treatment of cerebral aneurysms and the like usually has a coil and an elongation resistance member disposed in the lumen of the coil. The elongation resistance member suppresses elongation deformation of the coil during treatment, and for example, the one disclosed in Patent Document 1 is known. In Patent Document 1, a linear elongation resistance member (elongation prevention wire: 25) is disposed in the lumen of the coil (20).

[0003] The elongation resistance member is desirably formed in a wavy shape in order to facilitate smooth indwelling of the coil during treatment or alleviate excessive tension. As such members, the elongation resistance member (elongation resistant member: 105) disclosed in Patent Document 2 and the elongation resistance member (21) disclosed in Patent Document 3 are known.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of Invention

Problems to be Solved by the Invention

[0005] The stretch resistance member is made of resin or metal material, but in either case it consists of an extremely thin thread-like wire. Therefore, when forming the wire into a wavy shape, it is required to bend the wire smoothly and continuously without damaging it.

[0006] The object of the present invention is to provide a bending device that can smoothly bend wires used in the above-mentioned extension resistance members, i.e., extremely thin and delicate wires, into a wavy shape without damaging them, and a method for manufacturing wires. [Means for solving the problem]

[0007] The bending apparatus according to the present invention, which has been able to solve the above problems, is as follows. [1] A wire bending apparatus having a first gear having a first group of teeth and a second gear having a second group of teeth that rotates in synchronization with the first gear, With a wire positioned between the first tooth group and the second tooth group, the first gear and the second gear are rotated, causing the wire to come into contact with the first tooth group and the second tooth group and bend. A bending apparatus in which, even when the first gear and the second gear are rotated without a wire being placed between them, the first gear and the second gear do not come into contact with each other. [2] The bending apparatus according to [1], wherein the first gear is coaxially connected to a third gear having a third tooth group, and the third tooth group and the second tooth group come into contact when the third gear or the second gear is rotated. [3] The bending apparatus according to [2] wherein the diameter of the third gear is greater than the diameter of the first gear. [4] The bending apparatus according to [2] or [3], wherein either the second gear or the third gear is a driving gear and the other is a driven gear. [5] A bending apparatus according to any one of [1] to [4], wherein a bending section having the first tooth group and the second tooth group is formed, and a heating mechanism for heating the wire is provided on the wire pulling side of the bending section. [6] The bending apparatus according to [5], wherein a cooling mechanism for cooling the wire is provided on the wire feeding side of the bending section. [7] The wire is an extension resistance member placed in the lumen of an embolization coil that forms an in-vivo implantation device. [1] to [6] Bending apparatus

[0008] The wire manufacturing method according to the present invention, which has been able to solve the above problems, is as follows. [8] A bending apparatus comprising a first gear having a first tooth group and a second gear having a second tooth group and rotating synchronously with the first gear, wherein when the first gear and the second gear are rotated with a wire placed between them, the wire comes into contact with the first gear and the second tooth group and is bent, and when the first gear and the second gear are rotated without a wire placed between them, the first gear and the second tooth group do not come into contact with each other; A method for manufacturing a wire, comprising the step of feeding a wire between the first tooth group and the second tooth group while rotating the first gear and the second gear, and bending the wire. [9] The method for manufacturing a wire according to [8], wherein in the step of bending the wire, the first gear or the second gear is rotated at a speed of 5 rpm or more and 15 rpm or less. [Effects of the Invention]

[0009] According to the bending apparatus of the present invention, even extremely thin and delicate wires can be smoothly bent without damaging them.

[0010] According to the wire manufacturing method of the present invention, it is possible to produce and provide wires that are smoothly bent without damage, even if they are extremely thin and delicate. [Brief explanation of the drawing]

[0011] [Figure 1] A partially cut-out plan view showing the basic structure of a bending machine. [Figure 2] Front view showing the main parts of the bending machine in Figure 1. [Figure 3] Enlarged front view of the bending portion showing the state immediately before the wire bending step [Figure 4] Partially cutaway front view of the bending portion showing the wire bending step [Figure 5] Schematic diagram of a catheter including an in-vivo indwelling device [Figure 6] Cross-sectional view (partial side view) of the in-vivo indwelling device of Fig. 5 along the longitudinal axis of the coil

Modes for Carrying Out the Invention

[0012] Hereinafter, the present invention will be described more specifically based on the following embodiments. However, the present invention is not limited by the following embodiments from the outset, and it is of course possible to implement appropriate modifications within the range that can conform to the gist described before and after, and all of them are included in the technical scope of the present invention. In each drawing, for convenience, hatching, component reference numerals and the like may be omitted, and in such cases, the specification and other drawings shall be referred to. In addition, the dimensions of various members in the drawings are prioritized to contribute to the understanding of the features of the present invention, and thus may differ from the actual dimensions.

[0013] Fig. 1 and Fig. 2 show a bending apparatus B according to the present disclosure. That is, this is a wire rod 4 bending apparatus B having a first gear 1 with a first tooth 1t group, and a second gear 2 with a second tooth 2t group that rotates in synchronization with the first gear 1. By rotating the first gear 1 and the second gear 2 in a state where the wire rod 4 is arranged between the first tooth 1t group and the second tooth 2t group, the wire rod 4 abuts against the first tooth 1t group and the second tooth 2t group and is bent (see Fig. 4), and even if the first gear 1 and the second gear 2 are rotated in a state where the wire rod 4 is not arranged between the first tooth 1t group and the second tooth 2t group, the first tooth 1t group and the second tooth 2t group do not come into contact with each other (see Fig. 3), which is a feature of the apparatus.

[0014] According to this bending apparatus B, in a state where no wire rod is arranged between the first tooth 1t group and the second tooth 2t group, the first tooth 1t group and the second tooth 2t group do not come into contact with each other, that is, a gap is provided so that the first tooth 1t group and the second tooth 2t group are not in contact with each other. Therefore, the wire rod can be bent between the first tooth 1t and the second tooth 2t without being pinched more strongly than necessary and being cut or damaged. Accordingly, even a wire rod made of a relatively soft material such as synthetic resin can be smoothly bent while being prevented from being damaged.

[0015] To describe an example of bending a wire rod by the bending apparatus B, first, the wire rod 4 having a longitudinal direction above the bending portion 5 formed by the first gear 1 and the second gear 2 is arranged in a vertical orientation (see FIG. 3). Next, when the wire rod 4 is lowered to the bending portion 5 where the first gear 1 and the second gear 2 are rotating, the wire rod 4 comes into contact with the first tooth 1t group and the second tooth 2t group, is bent into a wavy shape, and is fed downward (see FIG. 4). The bending apparatus B of the present disclosure is an apparatus capable of continuously bending the wire rod 4 into a wavy shape.

[0016] As shown in FIG. 3, gaps E, F, G are secured between the first tooth 1t and the corresponding second tooth 2t in each of the tooth height direction and the tooth width direction, so that the non-contact state with each other is maintained. Accordingly, even in a state where the wire rod 4 is arranged and bent between the adjacent first tooth group 1t and second tooth group 2t in the bending portion 5 (see FIG. 4), the configuration is such that the action of strongly pinching the wire rod 4 caused by the first tooth group 1t and the second tooth group 2t attempting to directly abut each other does not occur.

[0017] For example, an experiment was conducted using a general gear transmission mechanism, feeding a wire into the meshing area between a pair of gears that mesh with each other to bend it into a wavy shape. In a general gear transmission mechanism, the teeth of each gear come into direct contact with each other, causing one gear to drive the other to rotate. In this case, the wire is strongly pinched as the teeth of each gear try to come into direct contact during the bending process. While it is possible to bend a relatively strong metal wire into a wavy shape, a relatively soft resin wire is prone to damage such as dents or breakage when strongly pinched, indicating room for improvement.

[0018] Therefore, in the bending apparatus B of this disclosure, the non-contact state between the first tooth group 1t and the second tooth group 2t is maintained by the synchronous rotation of the second gear 2 and the third gear 3 as described above, so that even extremely thin and delicate wires can be bent smoothly without damage. Accordingly, even when bending a wire 4 made of a very thin and soft material such as a wire for a stretch resistance member 40, it is possible to continuously and smoothly bend it into a wavy shape or simply bend it without causing damage such as dents, scratches, or breakage of the wire 4 during the bending process.

[0019] [Bending machine] As shown in Figures 1 and 2, the bending apparatus B comprises a first gear 1, a pair of third gears 3, 3 positioned on either side of the first gear 1, a first support shaft 7 through which these three gears 3, 1, and 3 are inserted, a second gear 2, and a second support shaft 8 through which the second gear 2 is inserted. The first gear 1 and the third gear 3 are connected coaxially. Preferably, the first support shaft 7, having a first axis P1, and the second support shaft 8, having a second axis P2, are pivotally supported using bearings 9 such as ball bearings so that they can rotate. Although not shown in the figures, preferably, the first and third gears 1, 3 and the first support shaft 7, and the second gear 2 and the second support shaft 8 are fitted together in a manner that prevents relative rotation (integrated rotation) by interlocking means such as serrations, splines, and key connections of various shapes.

[0020] The first group of teeth 1t of the first gear 1 and the second group of teeth 2t of the second gear 2 are meshed non-contact, and the third group of teeth 3t and the second group of teeth 2t of the third gear 3 are meshed in such a way that they rotate in conjunction. As shown in Figures 3 and 4, it is preferable that the third teeth 3t and the second teeth 2t mesh in a way that they are in contact with each other, so that the gear transmission mechanism 15 is formed by the third gears 3,3 and the second gear 2. It is preferable that the first gear 1 and the second gear 2 are meshed in such a way that the first group of teeth 1t and the second group of teeth 2t enter each other's tooth grooves 1m, 2m and overlap radially, but rotate synchronously in a non-contact state. A tooth groove refers to the space between adjacent teeth, and in the first gear 1, the space between adjacent first teeth 1t,1t is the first tooth groove 1m.

[0021] As an example, as shown in Figure 1, it is preferable, but not limited to, that the second support shaft 8 is driven and rotated by a drive source 14 such as an electric motor, and that the first gear 1 and each of the third gears 3, 3 rotate in synchronization with the second gear 2 (the first support shaft 7 may also be driven). The tooth profile of each tooth 1t to 3t may be a tooth that exhibits a substantially trapezoidal shape as shown in the figure when viewed in the direction of the axis P1 (or P3), as well as an involute tooth profile, a cycloidal tooth profile, or a trochoidal tooth profile, and is not limited to these. In the bending apparatus B according to this embodiment, the first gear 1 and the second gear 2 are rotated in synchronization so that the first tooth group 1t and the second tooth group 2t are in a non-contact meshing state by a gear transmission mechanism 15 in which the second gear 2 and the third gear 3 mesh and rotate in conjunction, and a structure in which the third gear 3 and the first gear 1 rotate as a single unit that cannot rotate relative to each other, but the apparatus is not limited to these configurations.

[0022] As shown in Figure 1, it is preferable that the first and third gears 1 and 3 rotate in the direction of arrow a, and the second gear 2 rotates in the direction of arrow b. If both the first support shaft 7 and the second support shaft 8 extend horizontally, as shown in Figure 3, the wire 4 can be fed into the bending section 5 by moving it downward in a vertical position with its up and down orientation. It is preferable that the diameter D3 of the third gear 3 is slightly larger than the diameter D1 of the first gear, and the diameter D2 of the second gear 2 is the same as the diameter D1 of the first gear 1, but these are not strict requirements. For example, the diameter of the first gear 1 is 23.6 mm and the diameter of the third gear 3 is 23.75 mm. Note that the "diameter" of the first to third gears 1 to 3 refers to the pitch circle diameter (reference circle diameter), and the same applies below.

[0023] As shown in Figures 1, 3, and 4, a heating mechanism 16 for warming the wire 4 is provided on the wire pull-in side (upper side of the paper in Figure 3) of the bending section 5, and a cooling mechanism 17 for cooling the wire 4 is provided on the wire feed-out side (lower side of the paper in Figure 3) of the bending section 5. One example of the heating mechanism 16 is a hot air blower with a blowing means such as a sirocco fan, and it is preferable, but not limited to, a configuration in which hot air is blown from the side onto the wire 4 as it moves downward toward the bending section 5. One example of the cooling mechanism 17 is a cold air blower with a blowing means such as a sirocco fan, and it is preferable, but not limited to, a configuration in which cold air is blown from the side onto the wire 4 as it is sent downward from the bending section 5 and moves downward.

[0024] By heating the wire 4 in the heating mechanism 16 before, preferably immediately before, the bending section 5 to make it flexible, the softened wire 4 can be smoothly bent in the bending section 5 with less processing resistance. Then, by cooling the wire 4 that has passed through the bending section 5 and been bent into the desired shape (which may be wavy or other shapes) in the cooling mechanism 17, the springback of the wire 4 after bending is suppressed or reduced, providing the advantage of obtaining a predetermined desired shape and quickly stabilizing the desired shape. Figure 4 shows an example in which a wavy stretch resistance member 40 is manufactured by bending the wire 4 into a wavy shape through the bending section 5.

[0025] In forming the corrugated wire 4 (tensile resistance member 40) by bending wire 4 into a wavy shape using bending device B, a resin monofilament was used as an example of the material for wire 4. Its specifications are shown in Table 1. The outer diameter was measured using a laser outer diameter measuring instrument. The definition of roundness is specified as the degree of deviation of a circular shape from a geometrically correct circle (JIS B 0682-1:2017), and in the diameter method, roundness = (maximum diameter - minimum diameter) / 2, but here, (1 - |(X-axis measurement value - Y-axis measurement value)| / average of measurement values ​​on both axes) × 100 (%) (|: represents the absolute value), five arbitrary points on the monofilament were measured, and the average value of the five measured points was calculated and expressed as "roundness". Instead of roundness, the flatness ratio "flatness ratio = (maximum diameter - minimum diameter) / maximum diameter" may be used. Elongation is the value up to fracture in a tensile test. Table 1 shows the specifications of the wire.

[0026] [Table 1]

[0027] To obtain a bending apparatus B that can bend the aforementioned monofilament wire 4 into the desired wavy shape, preliminary tests were conducted by bending the wire 4 using bending apparatus B with various modified processing conditions (specifications). As an example, Table 2 shows the processing conditions and results for a preliminary test to achieve processing conditions with a target amplitude of 50 μm and a target wavelength of 400 μm. Numbers 1 to 9 in the top row of Table 2 represent the wires used for the test, and nine different preliminary experiments were conducted. These nine wires are sometimes referred to as processing conditions 1 to 9. Amplitude is the width of the wave (wave height), and wavelength is the length of one pitch in the wave. Table 2 shows the processing conditions and results of the preliminary test (target amplitude 50 μm, target wavelength 400 μm).

[0028] [Table 2]

[0029] The notes for Table 2 are as follows: The diameters of the first and second gears and the third gear are all the diameters of the pitch circle. The modules of the first to third gears 1 to 3 are the value obtained by dividing the gear diameter (pitch circle diameter) by the number of teeth. [For reference, if the distance between adjacent teeth in the circumferential direction is defined as the pitch (circumferential pitch), then the pitches of each gear 1 to 3 are as follows: Pitch of the first and second gears 1 and 2 = 23.6 mm × π ÷ 236 = approximately 0.3142 mm, Pitch of the third gear 1 (for the third gear diameter of 23.75 mm in Table 2) = 23.75 mm × π ÷ 236 = approximately 0.3161 mm, Pitch of the third gear 2 (for the third gear diameter of 23.72 mm in Table 2) = 23.6 mm × π ÷ 236 = approximately 0.3157 mm]. The "RT" for the hot air temperature is room temperature, and one example is 25 degrees ± 1 degree. The gear clearance is the value at the location indicated by the symbol "F" in Figure 3 (the distance between the lower side of the first tooth 1t in the direction of rotation and the upper side of the second tooth 2t in the direction of rotation). It can also be represented at the locations indicated by the symbols E and G, but these are omitted here.

[0030] The diameter of the third gear 3 is preferably 23.72 mm, and is also preferably 23.71 mm to 23.73 mm, and 23.70 mm to 23.74 mm. The number of teeth of the first to third gears 1 to 3 is preferably 236, and is also preferably 234 to 238, and 232 to 240. The optimal range for the hot air temperature from the heating mechanism 16 is preferably 120 to 160°C, and is also preferably 110°C to 170°C, and 100°C to 180°C. The airflow rate per unit time [L (liters) / min] from the heating mechanism 16 is preferably 8, and is also preferably 7 to 9, and 6 to 10. For reference, an example of the distance W between the axes P1 of the first gear 1 and P2 of the second gear 2 is 23.66 mm.

[0031] From Table 2, regarding the point where the amplitude of the wire rod (amplitude Ave in Table 2) is close to the target amplitude of 50 μm, the processing conditions are excellent in the order of processing condition 8, processing condition 7, processing condition 9, processing condition 5 and 6, processing condition 4, processing condition 1 and 2, and processing condition 3. Regarding the point where the wavelength of the wire rod (amplitude Ave in Table 2) is close to the target wavelength of 400 μm, the processing conditions are excellent in the order of processing condition 3, processing condition 6, processing condition 2 and 9, processing condition 4, processing condition 5, processing condition 7, processing condition 8, and processing condition 1. In terms of amplitude, processing conditions 7, 8, and 9 are more preferable examples, and in terms of wavelength, processing conditions 3, 6, 2, and 9 are more preferable examples. Processing condition 3 is farthest from the target value in terms of amplitude, but closest to the target value in terms of wavelength. Each processing condition in the preliminary test shown in Table 2 is, as described above, an example performed to impart a wave shape with an amplitude of 50 μm and a wavelength of 400 μm to the wire rod 4 made of resin monofilament, and does not absolutely define the various specifications of the bending apparatus B.

[0032] [Alternative Embodiment of Bending Apparatus B] (1) It is possible to adopt a configuration in which the first gear 1 and the pair of third gears 3, 3 are supported by the first support shaft 7 so as to be relatively rotatable, the first gear 1 and the third gear 3 are connected so as not to be relatively rotatable, the second gear 2 is supported by the second support shaft 8 so as to be relatively rotatable, and a driving force is input to the second gear 2 or any one of the third gears 3.

[0033] (2) In the bending apparatus B according to the present embodiment, it is possible to omit the pair of third gears 3, 3, and instead control the rotation of one or both of the first support shaft 7 and the second support shaft 8, so as to adopt a configuration in which the first gear 1 and the second gear 2 are synchronously rotated such that the group of first teeth 1t and the group of second teeth 2t do not come into contact with each other.

[0034] (3) Various specifications such as the distance between the axis P1 of the first gear 1 and the axis P2 of the second gear 2, that is, the inter-axis distance W, the respective diameters of the first gear 1 and the second gear, and the radial overlap allowance c between the first tooth 1t and the second tooth 2t can be variously modified and set. The bending can theoretically be performed if the overlap allowance c is set to a value larger than -d (-d < c), where d is the thickness of the wire rod 4 (see FIG. 3).

[0035] (4) In the bending device B shown in Figures 1 and 2, the second gear 2 and the third gear 3 may be configured to have the same diameter, and the first gear 1 to have a smaller diameter than the third gear 3. For example, the second and third teeth 2t and 3t can be involute teeth to form a general gear transmission mechanism through the meshing of the second and third gears 2 and 3, and the shape and size of the first tooth 1t can be determined so that the first tooth 1t and the second tooth 2t do not come into contact.

[0036] (5) By appropriately setting the number of teeth 1t and 2t of the first and second gears 1 and 2, it is possible to create a bending device B that simply bends the wire 4. For example, a bending device can be considered that has a first gear 1 having a pair of adjacent first teeth 1t, 1t, and a second gear 2 having one second tooth 2t located between those first teeth 1t, 1t. Alternatively, in the bending device B shown in Figures 1 and 2, it is possible to bend the wire 4 in only one place by stopping the rotation drive of the device when the wire 4 is first bent (preferably then driving in reverse to discharge the wire 4).

[0037] [Method of manufacturing wire] Next, we will explain a method for manufacturing a wire that forms a corrugated wire 4 (= extension resistance member 40) using a bending device B. As shown in Figures 1, 2 and 3, 4, the wire manufacturing method according to the present disclosure is a wire manufacturing method comprising: a preparation step of preparing a bending apparatus B having a first gear 1 having a first group of teeth 1t and a second gear 2 having a second group of teeth 2t that rotates synchronously with the first gear 1, wherein the wire 4 is placed between the first group of teeth 1t and the second group of teeth 2t, and the wire 4 is bent by rotating the first gear 1 and the second gear 2 with the wire 4 placed between them, and the first group of teeth 1t and the second group of teeth 2t does not come into contact with each other even when the first gear 1 and the second gear 2 are rotated without the wire 4 placed between them; and a bending step of feeding the wire 4 between the first group of teeth 1t and the second group of teeth 2t while rotating the first gear 1 and the second gear 1 and bending the wire 4.

[0038] In other words, this is a manufacturing method in which a straight wire 4, which is a resin monofilament, is continuously bent using the bending apparatus B shown in Figures 1 and 2 to create a corrugated wire 4, as shown in Figures 3 and 4. In this case, it is preferable, but not limited to, that the first gear 1 (or second gear 2) be rotated at 5 rpm or more and 15 rpm or less. For example, 13 pm or more and 17 rpm or less, 11 pm or more and 17 rpm or less, or 7 rpm or more and 16 rpm or less are also preferable. Furthermore, it is preferable to suspend a weight M from the lower end of the wire 4 so that the wire 4 can be smoothly fed into the bending section 5.

[0039] In the preparation step, a wire 4 of a predetermined length is prepared, and a weight M is suspended from the lower end of the wire 4. The weight of the weight M is preferably 4 grams or more and 6 grams or less (e.g., 5 grams), and is also preferably 3 grams or more and 7 grams or 2 grams or more and 8 grams or less, but is not limited to these. As shown in Figure 3, in the bending step, the wire 4 with the weight M attached is fed into the bending section 5 of the processing device B by dropping it in from the pull-in side (upper side of the paper in Figure 3), which is the upper side in the rotation direction of the first and second gears 1 and 2. The weight M may be attached when the lower end of the wire 4 comes out of the bending section 5. The bending step includes a heating step in which the wire 4 is heated to an appropriate temperature range by a heating mechanism 16 before entering the bending section 5. For example, heating the wire 4 to 120 to 160°C makes it softer, which has the effect of allowing it to be bent more smoothly into a wavy shape in the bending section 5.

[0040] The wire 4 is forcibly bent in an alternating pattern by sequentially contacting one and the other of the first tooth 1t and the second tooth 2t, which are located on opposite sides of the wire 4 and rotate synchronously. As shown in Figure 4, a wavy wire 4 is produced by passing through the bending section 5. Even if the wire 4 is extremely thin and light, the downward tensile action of the weight M attached to the lower end allows the bending process to continue smoothly without the wire 4 getting entangled with the first and second teeth 1t and 2t or wrapped around the first and second gears 1 and 2, which is preferable. The cooling mechanism 17 provided on the wire feeding side of the bending section 5 cools the wavy wire 4, suppressing springback of the wire 4 after passing through the bending section 5 and the bending back action of the weight M, making it possible to produce a wire 4 with a stable wavy shape.

[0041] Next, we will describe an example of the use of a corrugated wire 4, which is produced by bending a wire 4 into a corrugated shape using a wire manufacturing method with a bending device B. As an example, we will now describe an in-vivo implantation device that uses a stretch-resistant member 40 made of corrugated wire 4.

[0042] [Intra-biovascular devices] Examples of the use of in vivo implantable devices include embolization to promote thrombosis at target sites such as cerebral aneurysms, head and neck aneurysms, arteriovenous malformations, arteriovenous fistulas, pulmonary vascular malformations, renal vascular malformations, renal artery aneurysms, and abdominal aneurysms. Among these, in vivo implantable devices for cerebral aneurysms are preferred. The shape of the aneurysm can be fusiform or saccular.

[0043] Figure 5 is a schematic diagram of catheter A including the in-vivo implantation device S1 and pusher 55, and Figure 6 is a cross-sectional view (partially a side view) of the in-vivo implantation device S1 along the longitudinal axis direction of the coil. As shown in Figure 6, in the in-vivo implantation device S1, the coil 10 has a longitudinal axis direction x, a radial direction y, and a circumferential direction z. The coil 10 has a distal end 10a and a proximal end 10b along the longitudinal axis direction x. The proximal side of the coil 10 refers to the direction toward the user or operator's hand with respect to the longitudinal axis direction x of the coil 10, and the distal side refers to the opposite direction from the proximal side, i.e., the direction toward the target of treatment. In Figure 6, the right side of the figure is the proximal side, and the left side of the figure is the distal side. The radial direction y of the coil 10 refers to the radial direction of the coil 10, and in the radial direction y, inward refers to the direction toward the longitudinal axis center of the coil 10, and outward refers to the direction extending radially from the longitudinal axis center on the opposite side from the inward direction. The circumferential direction z of coil 10 refers to the direction around the longitudinal axis.

[0044] As shown in Figure 6, the coil 10 has an outer circumferential surface 12 and an inner circumferential surface 13. The surface of the coil 10 includes the outer circumferential surface 12 and the inner circumferential surface 13. It is preferable that the coil 10 has a lumen 11 extending in the longitudinal axis direction x. The outer circumferential surface 12 of the coil 10 faces the outside of the coil 10, i.e., the outside in the radial direction y, and the inner circumferential surface 13 of the coil 10 faces the lumen 11. It is preferable that a stretch resistance member 40, which will be described later, is placed in the lumen 11.

[0045] As shown in Figures 5 and 6, the coil 10 is preferably constructed by winding one or more wires 31 in a helical manner. Examples of wires 31 include single wires, stranded wires, and coiled wires, with single wires being preferred.

[0046] The wire 31 is preferably biocompatible and flexible. Examples of materials that make up the wire 31 include platinum, gold, titanium, tungsten and their alloys, stainless steel, and other metallic materials or combinations thereof. Among these, it is more preferable that the wire 31 is made of a platinum-tungsten alloy.

[0047] It is preferable that the coil 10 has a constant outer diameter in the longitudinal axis direction x. A constant outer diameter means that the outer diameter of the coil 10 is substantially constant over the entire longitudinal axis direction x, and includes cases where the change in the outer diameter of the coil 10 over the entire longitudinal axis direction x is within ±5%.

[0048] As shown in Figure 6, the in-vivo implantation device S1 preferably has an extension resistance member 40 positioned in the lumen 11 of the coil 10. The extension resistance member 40 suppresses the stretching of the coil 10 in the longitudinal axis direction x during operation. The extension resistance member 40 is preferably formed from a long member consisting of a single wire or stranded wire. The extension resistance member 40 has a longitudinal axis direction and has a first end and a second end in that longitudinal axis direction. The extension resistance member 40 is preferably composed of one or more layers in the radial direction perpendicular to the longitudinal axis direction. The extension resistance member 40 preferably has an inner layer composed of stranded wire made of multiple wires and an outer layer provided outside the inner layer and containing a resin composition. It is preferable that one or more extension resistance members 40 are positioned in the lumen 11.

[0049] The stretch resistance member 40, which is made of a wavy wire 4, is preferably made of resin or metal. Examples of resins that make up the stretch resistance member 40 include polyester resins such as polyethylene terephthalate, polyamide resins such as nylon, and polyolefin resins such as polyethylene and polypropylene. Being made of resin increases flexibility and improves the delivery performance of the in-vivo implant S1. Also, if the stretch resistance member 40 is made of resin, fracture due to metal fatigue during delivery can be eliminated. By making the length of the stretch resistance member 40 longer than the length of the coil 10, or by using a material that is easily stretched for the stretch resistance member 40, the tension caused by the end of the coil 10 stretching in a straight line due to insufficient length of the stretch resistance member 40 when the coil 10 is placed in the nodule can be alleviated. Examples of metals that make up the stretch resistance member 40 include platinum, gold, rhodium, palladium, rhenium, silver, nickel, titanium, tantalum, tungsten and their alloys, and stainless steel.

[0050] The extension resistance member 40 is made of a different material from or the same material as the wire 31 that constitutes the coil 10. For example, a combination in which the coil 10 is made of a platinum-tungsten alloy and the extension resistance member 40 is made of polypropylene resin is conceivable, but is not limited to this.

[0051] The shape of the extension resistance member 40 can be various, such as a circular shape, an oval shape, a polygonal shape, or a combination thereof, with the cross-sectional shape perpendicular to the longitudinal axis.

[0052] To facilitate the placement of the stretch resistance member 40 in the lumen 11, the outer diameter of the stretch resistance member 40 is preferably less than half the inner diameter of the coil 10, and more preferably one-third or less. To prevent the stretch resistance member 40 from breaking, the outer diameter of the stretch resistance member 40 is preferably one-fifteenth or more the inner diameter of the coil 10, and more preferably one-tenth or more. The stretch resistance member 40 can be linear, wavy, helical, or a combination thereof.

[0053] The first end of the extension resistance member 40 may be connected to the distal end of the coil 10, specifically to the distal end of the wire 31 that constitutes the coil 10. The second end of the extension resistance member 40 may be connected to the proximal end of the coil 10, specifically to the proximal end of the wire 31. The second end of the extension resistance member 40 may be connected to the connection portion 50 that connects the coil 10 and the pusher 55. The extension resistance member 40 may be placed in the lumen 11 in a state where it is folded back in the middle of its longitudinal axis. In that case, it is preferable that the folded portion 41 of the extension resistance member 40 is connected to the distal or proximal end of the coil 10, and the first end and the second end are connected to the proximal or distal end of the coil 10, or to the distal end of the connection portion 50. For example, in Figure 2, the extension resistance member 40 has a folded portion 41 that is folded back in the middle of the longitudinal axis direction, the folded portion 41 is connected to the distal end of the coil 10, and the first end and the second end are connected to the connection portion 50.

[0054] Methods for connecting the extension resistance member 40 to other members include physical fixing methods such as welding, crimping, adhesive bonding, engagement, linking, binding, ligation, or combinations thereof. Here, "connection" includes both forms in which the two elements are directly connected and forms in which the two elements are indirectly connected through one or more other elements. [Explanation of Symbols]

[0055] 1. First gear 1t First tooth 2. Second Glucose 2t 2nd tooth 3 Third gear 3t 3rd tooth 4 wire rod 5. Bending section 10 coils 11 Lumen 16 Heating mechanism 17 Cooling mechanism 40 Extension resistance member B Bending machine S1 Intra-vivo device

Claims

1. A wire bending apparatus having a first gear having a first group of teeth and a second gear having a second group of teeth that rotates in synchronization with the first gear, With a wire positioned between the first tooth group and the second tooth group, the first gear and the second gear are rotated, causing the wire to come into contact with the first tooth group and the second tooth group and bend. A bending apparatus in which, even when the first gear and the second gear are rotated without a wire being placed between them, the first gear and the second gear do not come into contact with each other.

2. The bending apparatus according to claim 1, wherein the first gear is coaxially connected to a third gear having a third tooth group, and the third tooth group and the second tooth group come into contact when the third gear or the second gear is rotated.

3. The bending apparatus according to claim 2, wherein the diameter of the third gear is greater than the diameter of the first gear.

4. The bending apparatus according to claim 2 or 3, wherein either the second gear or the third gear is a driving gear and the other is a driven gear.

5. A bending section having the first tooth group and the second tooth group is formed, The bending apparatus according to claim 1, wherein a heating mechanism for heating the wire is provided on the wire pull-in side of the bending section.

6. The bending apparatus according to claim 5, wherein a cooling mechanism for cooling the wire is provided on the wire feeding side of the bending section.

7. The bending apparatus according to any one of claims 1 to 3, 5, or 6, wherein the wire is an extension-resistant member disposed in the lumen of a coil forming an in-vivo implantable device.

8. A bending apparatus comprising: a first gear having a first tooth group; a second gear having a second tooth group and rotating synchronously with the first gear, wherein when the first gear and the second gear are rotated with a wire placed between them, the wire contacts the first gear and the second tooth group and is bent; and when the first gear and the second gear are rotated without a wire placed between them, the first gear and the second tooth group do not come into contact with each other; A method for manufacturing a wire, comprising the step of feeding a wire between the first tooth group and the second tooth group while rotating the first gear and the second gear, and bending the wire.

9. The method for manufacturing a wire according to claim 8, wherein in the step of bending the wire, the first gear or the second gear is rotated at 5 rpm or more and 15 rpm or less.

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