Conductive wire and method for manufacturing the same

Abstract

To provide a conductive wire having a simple structure to reduce electrical resistance.SOLUTION: A conductive wire 1 comprises a conductive part 3 and an insulating part 5. The conductive part 3 having a linear or rod-like shape includes a sheet-like conductive sheet 2 containing carbon as main component, which is wound or folded such that in a specified region 2a of the sheet, a face 2b and the other face 2c directed toward the thickness direction come in contact with the faces directed toward the thickness direction of other regions 2d and 2e of the conductive sheet 2, respectively. The insulating part 5 includes an insulating sheet 4 wound or folded to cover the outside of the conductive part 3.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a conductive wire including a conductor portion mainly composed of carbon, and a method for manufacturing the conductive wire.

Background Art

[0002] Conventionally, a conductive wire using carbon nanotubes as a conductor mainly composed of carbon has been proposed. In the following description, carbon nanotubes are denoted as CNTs.

[0003] The conductive wire described in Patent Document 1 is configured by winding or folding, in a direction orthogonal to the longitudinal direction of a sheet-like covering member or in another direction, a conductor formed of CNTs on a part of the surface of the sheet-like covering member formed in a strip shape. In other words, this conductive wire is configured by winding or folding together a conductor in the form of a sheet with a covering member disposed on the entire surface of one side in the thickness direction of the sheet-like conductor. Patent Document 1 describes that the covering member maintains its shape and the conductor conducts electricity.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the conductive wire described in Patent Document 1 has a configuration in which a covering member is necessarily disposed on one surface in the thickness direction of the conductor. Therefore, in a cross-sectional view perpendicular to the axis, this conductive wire has a tendency for the ratio of the area occupied by the covering member to increase and the ratio of the area occupied by the conductor portion to decrease. Therefore, when the covering member is made of an insulator, this conductive wire has a problem that the electrical resistance increases.

[0006] In view of the above points, an object of the present invention is to provide a conductive wire capable of reducing electrical resistance with a simple configuration and a method for manufacturing the conductive wire.

Means for Solving the Problems

[0007] To achieve the above object, the conductive wire according to the invention of claim 1 includes a conductor part (3) and an insulating part (4). The conductor part is formed in a linear or rod shape by being wound or folded such that the surfaces facing the thickness direction of another part (2d, 2e) in the conductor sheet contact one surface (2b) and the other surface (2c) facing the thickness direction among the predetermined parts (2a) in the sheet-like conductor sheet (2) mainly composed of carbon. The insulating part is wound or folded so as to cover the outside of the conductor part with the insulating sheet (4).

[0008] According to this, the conductive wire has a configuration in which the insulating part covers the outside of the conductor part formed by being wound or folded while only the conductor sheet contacts both surfaces in the thickness direction. Therefore, in a cross-sectional view perpendicular to the axis, it is possible to increase the ratio of the area occupied by the conductor part with respect to the ratio of the area occupied by the insulating part. Accordingly, this conductive wire can reduce the electrical resistance by increasing the cross-sectional area of the conductor part.

[0009] The invention according to claim 9 is a method for manufacturing a conductive wire, and includes the following steps. A step (S10) of preparing a sheet-like conductor sheet (2) mainly composed of carbon. A step (S20) of preparing an insulating sheet in which the area of the surface facing the thickness direction in the insulating sheet (4) is smaller than the area of the surface facing the thickness direction in the conductor sheet. A step (S30) of providing an insulating sheet on a part of the conductor sheet. A step (S40) of forming a linear or rod-shaped conductor part (3) and an insulating part (5) covering the outside of the conductor part by winding or folding the conductor sheet and the insulating sheet from the part of the conductor sheet where the insulating sheet is not provided toward the part of the conductor sheet where the insulating sheet is provided.

[0010] According to this, the conductive wire manufactured by this manufacturing method has a configuration in which only the conductor sheet is wound or folded while being in contact with both surfaces in the thickness direction, and the insulating portion covers the outside of the formed conductor portion. Therefore, by this manufacturing method, it is possible to increase the ratio of the area occupied by the conductor portion to the ratio of the area occupied by the insulating portion in a cross-sectional view perpendicular to the axis of the conductive wire. Accordingly, by this manufacturing method, a conductive wire with low electrical resistance can be manufactured.

[0011] Note that the reference numerals in parentheses attached to each component etc. indicate an example of the correspondence relationship between the component etc. and the specific components etc. described in the embodiments described later.

Brief Description of the Drawings

[0012]

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

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are denoted by the same reference numerals, and the description thereof will be omitted.

[0014] (First Embodiment) The first embodiment will be described with reference to FIGS. 1 to 4. FIG. 1 shows the state before winding the conductor sheet 2 and the insulating sheet 4, and FIGS. 2 and 3 show the completed conductive wire 1 obtained by winding the conductor sheet 2 and the insulating sheet 4.

[0015] In FIG. 1, the longitudinal direction, thickness direction, and width direction in the conductor sheet 2 and the insulating sheet 4 are shown in three-dimensional coordinates. Both the conductor sheet 2 and the insulating sheet 4 are formed such that the length in the longitudinal direction is longer than the length in the width direction.

[0016] Note that FIG. 3 shows a cross-section perpendicular to the axis of the conductive wire 1. However, for easy understanding of each component, hatching is applied to the insulating portion 5, and no hatching is applied to the conductor portion 3. This is the same for the cross-sectional views of the conductive wire 1 referred to in each of the embodiments described later.

[0017] As shown in FIGS. 1 to 3, the conductive wire 1 of the first embodiment includes a conductor portion 3 formed by winding a sheet-like conductor sheet 2, and an insulating portion 5 formed by winding so as to cover the outside of the conductor portion 3 with an insulating sheet 4.

[0018] The conductor sheet 2 shown in FIG. 1 is composed mainly of carbon and is composed of CNTs in the first embodiment. The CNTs constituting the conductor sheet 2 are, for example, those having a relatively high degree of orientation in the longitudinal direction, not containing a binder or a dispersant, and having no adhesiveness by themselves. Such a conductor sheet 2 is constituted, for example, by forming a CNT tape using a CNT dispersion liquid with chlorosulfonic acid as a dispersant, as described in Japanese Patent Application Laid-Open No. 2011-502925. Alternatively, the conductor sheet 2 may be constituted by a CNT sheet obtained by pulling out a CNT web from a CNT array synthesized perpendicular to a substrate.

[0019] The insulating sheet 4 shown in FIG. 1 is composed of an insulating resin or the like. The insulating sheet 4 is used such that the area of the surface facing the thickness direction is smaller than the area of the surface facing the thickness direction in the conductor sheet 2. The insulating sheet 4 is provided on a part of the conductor sheet 2. In the first embodiment, the insulating sheet 4 is provided so as to overlap in the thickness direction of the conductor sheet 2 at a portion on one side in the width direction of the surface facing the thickness direction in the conductor sheet 2. The insulating sheet 4 and the conductor sheet 2 may be fixed with an adhesive or an adhesive not shown.

[0020] The conductive wire 1 shown in FIGS. 2 and 3 is formed by winding or folding the conductor sheet 2 and the insulating sheet 4 in the state shown in FIG. 1. Specifically, the conductive wire 1 is formed by winding or folding the conductor sheet 2 and the insulating sheet 4 from the portion of the conductor sheet 2 where the insulating sheet 4 is not provided to the portion of the conductor sheet 2 where the insulating sheet 4 is provided. In the first embodiment, as shown by the arrow R in FIG. 1, the conductive wire 1 first winds only the conductor sheet 2 along the direction orthogonal to the longitudinal direction of the conductor sheet 2, and then, at the portion where the insulating sheet 4 and the conductor sheet 2 overlap, winds the insulating sheet 4 and the conductor sheet 2 together.

[0021] As shown in FIGS. 2 and 3, in the conductive wire 1, the portion where only the conductor sheet 2 is wound to form a linear or rod-shaped portion is called the conductor portion 3. Also, in the conductive wire 1, the portion where the insulating sheet 4 is wound so as to cover the outside of the conductor portion 3 is called the insulating portion 5. That is, the conductive wire 1 includes the conductor portion 3 and the insulating portion 5.

[0022] As shown in FIG. 3, the conductor portion 3 is formed by winding only the conductor sheet 2 in a spiral shape. Specifically, the conductor portion 3 is wound such that the surfaces facing the thickness direction of one surface 2b and the other surface 2c of a predetermined portion 2a of the conductor sheet 2 are in contact with the surfaces facing the thickness direction of another portion 2d, 2e of the conductor sheet 2. That is, the conductor portion 3 is formed by winding the conductor sheet 2 three or more times in the thickness direction.

[0023] Also, as shown in FIGS. 2 and 3, the insulating portion 5 covers the outer periphery of the conductive wire 1 one or more times in the circumferential direction. Note that the portion where the insulating sheets 4 of the insulating portion 5 are in contact with each other or overlap in the thickness direction may be fixed with an adhesive or an adhesive (not shown) so that the conductor portion 3 and the insulating portion 5 do not unwind.

[0024] Next, the manufacturing process of the conductive wire 1 will be described.

[0025] As shown in FIG. 4, first, in step S10, a conductor sheet 2 is prepared. As described above, the conductor sheet 2 is composed of a CNT sheet.

[0026] Next, in step S20, an insulating sheet 4 is prepared.

[0027] Subsequently, in step S30, the insulating sheet 4 is provided by overlapping it in the thickness direction of the conductor sheet 2 on one side of the width direction among the surfaces facing the thickness direction in the conductor sheet 2.

[0028] Next, in step S40, the conductor sheet 2 is wound from the portion of the conductor sheet 2 where the insulating sheet 4 is not provided toward the portion of the conductor sheet 2 where the insulating sheet 4 is provided. And at the portion where the conductor sheet 2 and the insulating sheet 4 overlap, the conductor sheet 2 and the insulating sheet 4 are wound together. Note that at the end of winding, the portion where the insulating sheets 4 of the insulating portion 5 are in contact or overlap with each other in the thickness direction may be fixed with an adhesive or a sticky agent.

[0029] Thereby, the conductive wire 1 is completed. The conductive wire 1 manufactured in this way has a configuration in which the insulating portion 5 covers the outside of the conductor portion 3 formed by winding while only the conductor sheet 2 is in contact with both surfaces in the thickness direction. Therefore, by this manufacturing method, it is possible to increase the ratio of the area occupied by the conductor portion 3 with respect to the ratio of the area occupied by the insulating portion 5 in a cross-sectional view perpendicular to the axis. Accordingly, by this manufacturing method, a conductive wire 1 with low electrical resistance can be manufactured.

[0030] For comparison with the conductive wire 1 of the first embodiment described above, the conductive wire 10 of the comparative example will be described with reference to FIGS. 5 to 7.

[0031] FIG. 5 shows the state before the conductor sheet 2 and the insulating sheet 4 are wound, and FIGS. 6 and 7 show the completed conductive wire 10 in a state where the conductor sheet 2 and the insulating sheet 4 are wound. As shown in FIGS. 5 to 7, the conductive wire 10 of the comparative example also includes a conductor portion 3 formed by winding the sheet-like conductor sheet 2 and an insulating portion 5 formed by winding the insulating sheet 4.

[0032] The materials of the conductor sheet 2 and the insulating sheet 4 are the same as those described in the first embodiment. However, in the comparative example, as shown in FIG. 5, the insulating sheet 4 is provided so as to overlap the conductor sheet 2 in the thickness direction over the entire surface facing the thickness direction of the conductor sheet 2. Then, as shown by the arrow R in FIG. 5, the conductive wire 1 is formed by winding the conductor sheet 2 and the insulating sheet 4 together along a direction orthogonal to the longitudinal direction.

[0033] As shown in FIG. 7, in a cross-sectional view perpendicular to the axial direction, the conductive wire 10 is wound in a spiral shape such that the conductor sheet 2 and the insulating sheet 4 overlap alternately in the thickness direction. Specifically, the conductor portion 3 is wound such that the surfaces of the insulating sheet 4 facing the thickness direction are in contact with one surface and the other surface facing the thickness direction among predetermined portions of the conductor sheet 2.

[0034] The conductive wire 10 of the comparative example having the above-described configuration has a lower filling rate of the conductor portion 3 than the conductive wire 1 of the first embodiment. That is, in a cross-sectional view perpendicular to the axis, the conductive wire 10 of the comparative example has a larger ratio of the area occupied by the insulating portion 5 and a smaller ratio of the area occupied by the conductor portion 3 than the conductive wire 1 of the first embodiment. Specifically, for example, assuming that the width of the conductor sheet 2 in the state before winding is 10 mm, the thickness of the conductor sheet 2 is 0.02 mm, and the thickness of the insulating sheet 4 is 0.02 mm, the cross-sectional area of the conductor portion 3 of the conductive wire 10 of the comparative example is reduced by 40% compared to the conductive wire 1 of the first embodiment. Therefore, the conductive wire 10 of the comparative example has a larger electrical resistance than the conductive wire 1 of the first embodiment.

[0035] The conductive wire 1 of the first embodiment has the following operational effects with respect to the conductive wire 10 of the comparative example described above. (1) In the conductive wire 1 of the first embodiment, the conductor portion 3 is wound such that the surfaces facing the thickness direction of one surface and the other surface of a predetermined portion of the conductor sheet 2 are in contact with the surfaces facing the thickness direction of another portion of the conductor sheet 2. The insulating portion 5 is wound so as to cover the outside of the conductor portion 3 with the insulating sheet 4. According to this, the conductive wire 1 has a configuration in which the insulating portion 5 covers the outside of the conductor portion 3 formed by winding while only the conductor sheet 2 is in contact with both surfaces in the thickness direction. Therefore, in a cross-sectional view perpendicular to the axis, the conductive wire 1 can increase the ratio of the area occupied by the conductor portion 3 with respect to the ratio of the area occupied by the insulating portion 5. Accordingly, this conductive wire 1 can reduce the electrical resistance by increasing the cross-sectional area of the conductor portion 3.

[0036] (2) In the conductive wire 1 of the first embodiment, the conductor portion 3 is formed in a linear or rod shape in a state where only the conductor sheet 2 is wound along a direction orthogonal to the longitudinal direction of the conductor sheet 2. According to this, when the conductor sheet 2 contains CNT as a main component, generally, the conductor sheet 2 has a high alignment rate of CNT in the longitudinal direction. In that case, if the conductor sheet 2 is wound or folded along a direction orthogonal to the longitudinal direction of the conductor sheet 2 to form the conductor portion 3, the alignment rate of CNT becomes high in the direction in which the axis of the conductive wire 1 extends, so that the electrical resistance of the conductive wire 1 can be made smaller.

[0037] In this specification, "along a direction orthogonal to the longitudinal direction of the conductor sheet 2" includes not only the direction orthogonal to the longitudinal direction of the conductor sheet 2 but also a direction slightly deviated from the direction orthogonal to the longitudinal direction of the conductor sheet 2 (for example, a direction deviated by about ±10°).

[0038] (3) The manufacturing method of the conductive wire 1 of the first embodiment includes a step S10 of preparing the conductor sheet 2, a step S20 of preparing the insulating sheet 4 having an area smaller than that of the conductor sheet 2, a step S30 of providing the insulating sheet 4 on a part of the conductor sheet 2, and a step S40 of winding the conductor sheet 2 and the insulating sheet 4. According to this, the conductive wire 1 manufactured by this manufacturing method has a configuration in which the insulating portion 5 covers the outside of the conductor portion 3 formed by winding while only the conductor sheet 2 is in contact with both surfaces in the thickness direction. Therefore, by this manufacturing method, it is possible to increase the ratio of the area occupied by the conductor portion 3 to the ratio of the area occupied by the insulating portion 5 in a cross-sectional view perpendicular to the axis of the conductive wire 1. Therefore, by this manufacturing method, a conductive wire 1 with low electrical resistance can be manufactured.

[0039] (Second Embodiment) The second embodiment will be described with reference to FIGS. 8 and 9. FIG. 8 shows the state before winding the conductor sheet 2 and the insulating sheets 4a and 4b, and FIG. 9 shows a cross-section perpendicular to the axis in the completed conductive wire 1. The conductive wire 1 of the second embodiment also includes a conductor portion 3 formed by winding the conductor sheet 2 and an insulating portion 5 formed by winding so as to cover the outside of the conductor portion 3 with the insulating sheets 4a and 4b.

[0040] As shown in FIG. 8, in the second embodiment, the insulating sheets 4a and 4b are provided so as to overlap in the thickness direction of the conductor sheet 2 at a portion on one side in the width direction and a portion on one side in the longitudinal direction among the surfaces facing the thickness direction in the conductor sheet 2. Then, as shown by the arrow R and the broken-line arrow in FIG. 8, the conductive wire 1 is formed by winding the conductor sheet 2 and the insulating sheets 4a and 4b along a direction other than the direction perpendicular to the longitudinal direction. By providing the insulating sheet 4b, even when winding along a direction other than the direction perpendicular to the longitudinal direction, the outside of the conductive portion 3 can be covered without leakage with the insulating sheet.

[0041] As shown in FIG. 9, the cross-sectional shape of the conductive wire 1 of the second embodiment is also substantially the same as the cross-sectional shape of the conductive wire 1 described in the first embodiment.

[0042] The conductive wire 1 of the second embodiment described above also exhibits the same operational effects as the conductive wire 1 of the first embodiment.

[0043] (Third Embodiment) The third embodiment will be described with reference to FIGS. 10 and 11. FIG. 10 shows the state before folding the conductor sheet 2 and the insulating sheet 4, and FIG. 11 shows a cross section perpendicular to the axis in the completed conductive wire 1. The conductive wire 1 of the third embodiment includes a conductor portion 3 formed by folding the conductor sheet 2 and an insulating portion 5 formed by folding so as to cover the outside of the conductor portion 3 with the insulating sheet 4.

[0044] As shown in FIG. 10, in the third embodiment, the insulating sheet 4 is provided so as to overlap in the thickness direction of the conductor sheet 2 at a portion on one side in the width direction among the surfaces facing the thickness direction in the conductor sheet 2. Then, as shown by the arrow F in FIG. 10, the conductive wire 1 is formed by folding the conductor sheet 2 and the insulating sheet 4 along a direction orthogonal to the longitudinal direction. Specifically, the operation of folding at a position a predetermined distance away from the end of the conductor sheet 2 on the side opposite to the insulating sheet 4 in the direction orthogonal to the longitudinal direction, and then folding at a position a predetermined distance away from there in the direction orthogonal to the longitudinal direction is repeated.

[0045] As shown in FIG. 11, the cross-sectional shape of the conductive wire 1 of the third embodiment is a rounded rectangle formed by two outwardly convex semicircles and parallel lines connecting the two semicircles. Note that the cross-sectional shape of the conductive wire 1 of the third embodiment may be a rectangle with rounded corners.

[0046] The conductive wire 1 of the third embodiment described above also exhibits the same effects as the conductive wire 1 of the first embodiment. Furthermore, since the cross-sectional shape perpendicular to the axis of the conductive wire 1 of the third embodiment is a rounded rectangle or a rectangle with rounded corners, for example, when used as a winding of a coil, it is possible to improve the occupation ratio.

[0047] (Fourth Embodiment) The fourth embodiment will be described with reference to FIGS. 12 to 14. FIG. 12 shows the state before the conductor sheet 2 and the insulating sheet 4 are wound, and FIG. 13 shows a cross section perpendicular to the axis in the completed conductive wire 1. The conductive wire 1 of the fourth embodiment includes a core material 6 provided at the center of the conductor portion 3 in addition to the conductor portion 3 and the insulating portion 5. The core material 6 is a rod-shaped member. As the core material 6, for example, a metal wire such as gold, silver, copper, aluminum, iron, titanium, or a thermoplastic resin member is used.

[0048] As shown in FIG. 12, in the fourth embodiment, in the state before the conductor sheet 2 and the insulating sheet 4 are wound, the insulating sheet 4 is provided on one side in the width direction of the surface of the conductor sheet 2 facing in the thickness direction, overlapping in the thickness direction of the conductor sheet 2. The core material 6 is disposed at a portion of the conductor sheet 2 opposite to the insulating sheet 4. Further, the core material 6 is disposed so as to extend along the longitudinal direction of the conductor sheet 2.

[0049] As shown by the arrow R in FIG. 12, the conductive wire 1 is formed by winding the conductor sheet 2 and the insulating sheet 4 along a direction orthogonal to the longitudinal direction. At that time, the conductor sheet 2 is wound around the core material 6, and then, at the portion where the insulating sheet 4 and the conductor sheet 2 overlap, the insulating sheet 4 and the conductor sheet 2 are wound together.

[0050] As shown in FIG. 11, the conductive wire 1 of the fourth embodiment has a configuration in which a core material 6 is provided at the center.

[0051] Next, the manufacturing process of the conductive wire 1 of the fourth embodiment will be described.

[0052] As shown in FIG. 14, steps S10 to S30 are the same as steps S10 to S30 described in the first embodiment. That is, in step S10, the conductor sheet 2 is prepared. In step S20, the insulating sheet 4 is prepared. In step S30, the insulating sheet 4 is provided on one side in the width direction of the surface of the conductor sheet 2 facing in the thickness direction, overlapping in the thickness direction of the conductor sheet 2.

[0053] Subsequently, in step S35, the core material 6 is disposed at a portion of the conductor sheet 2 on the side opposite to the insulating sheet 4. The core material 6 is disposed so as to extend along the longitudinal direction.

[0054] Next, in step S40, the conductor sheet 2 is wound around the core material 6. Subsequently, at the portion where the insulating sheet 4 and the conductor sheet 2 overlap, the insulating sheet 4 and the conductor sheet 2 are wound together. Note that at the end of winding, the portion where the insulating sheets 4 of the insulating portion 5 are in contact with each other or overlap in the thickness direction may be fixed with an adhesive or a pressure-sensitive adhesive.

[0055] Thereby, the conductive wire 1 is completed. The conductive wire 1 manufactured in this way has a configuration in which the core material 6 is disposed at the center portion. Note that the outside of the core material 6 is covered with the insulating portion 5 in a configuration in which only the conductor sheet 2 is wound while being in contact with both surfaces in the thickness direction, similar to the first embodiment and the like.

[0056] The conductive wire 1 of the fourth embodiment described above also exhibits the same operational effects as the conductive wire 1 of the first embodiment. Furthermore, in the conductive wire 1 of the fourth embodiment, by disposing the core material 6 at the center of the conductor portion 3, in the manufacturing process, the operation of winding the conductor sheet 2 around the core material 6 can be easily performed.

[0057] Also, in the fourth embodiment, it is exemplified that the core material 6 disposed at the center of the conductor portion 3 is a metal wire such as gold, silver, copper, aluminum, iron, or titanium. According to this, it is possible to increase the bending strength of the completed conductive wire 1. Furthermore, since the metal wire has conductivity and is easily plastically deformed into an arbitrary shape, it is possible to suppress a decrease in the electrical resistance of the conductive wire 1 and improve the formability of the conductive wire 1. Therefore, the conductive wire 1 is suitable for applications such as coils, for example.

[0058] Furthermore, in the fourth embodiment, it is exemplified that the core material 6 disposed at the center of the conductor portion 3 is a thermoplastic resin member. According to this, since the thermoplastic resin member has the property of being moldable into an arbitrary shape by heating, the moldability of the conductive wire 1 can be improved. Therefore, the conductive wire 1 is suitable for applications such as coils, for example.

[0059] (Fifth Embodiment) The fifth embodiment will be described with reference to FIGS. 15 and 16. FIG. 15 shows a cross section perpendicular to the axis in the completed conductive wire 1. The conductive wire 1 of the fifth embodiment has a hollow region 7 in the central part of the conductor portion 3.

[0060] The manufacturing process of the conductive wire 1 of the fifth embodiment will be described.

[0061] As shown in FIG. 16, steps S10 to S40 are the same as steps S10 to S40 described in the fourth embodiment. That is, in step S10, the conductor sheet 2 is prepared. In step S20, the insulating sheet 4 is prepared. In step S30, the insulating sheet 4 is provided by overlapping it in the thickness direction of the conductor sheet 2 on one side of the width direction among the surfaces facing the thickness direction in the conductor sheet 2. In step S35, the core material 6 is disposed at a portion of the conductor sheet 2 on the side opposite to the insulating sheet 4. In step S40, the conductor sheet 2 is wound around the core material 6, and at the portion where the insulating sheet 4 and the conductor sheet 2 overlap, the insulating sheet 4 and the conductor sheet 2 are wound together.

[0062] Subsequently, in step S50, by removing the core material 6 disposed in the central part of the conductor portion 3, a hollow region 7 is formed in the central part of the conductor portion 3. Thereby, the conductive wire 1 having the hollow region 7 in the central part of the conductor portion 3 is completed.

[0063] The conductive wire 1 of the fifth embodiment described above also exhibits the same operational effects as the conductive wire 1 of the first embodiment. Furthermore, since the conductive wire 1 of the fifth embodiment has a hollow region 7 in the central part of the conductor portion 3, the conductive wire 1 can be easily bent. Therefore, the conductive wire 1 is suitable for applications such as coils, for example.

[0064] (Sixth Embodiment) The sixth embodiment will be described with reference to FIGS. 17 and 18. FIG. 17 shows the state before the conductor sheet 2 and the insulating sheet 4 are wound, and FIG. 18 shows a perspective view of the completed conductive wire 1. The conductive wire 1 of the sixth embodiment also includes a conductor portion 3 formed by winding the conductor sheet 2, and an insulating portion 5 formed by winding so as to cover the outside of the conductor portion 3 with the insulating sheet 4.

[0065] As shown in FIG. 17, in the sixth embodiment, the length of the insulating sheet 4 in the longitudinal direction is shorter than the length of the conductor sheet 2 in the longitudinal direction. Therefore, the insulating sheet 4 is arranged so as to exclude the longitudinal end portion 2f of the conductor sheet 2. Then, as shown by the arrow R in FIG. 17, the conductive wire 1 is formed by winding the conductor sheet 2 and the insulating sheet 4 along a direction orthogonal to the longitudinal direction. As a result, as shown in FIG. 18, the conductive wire 1 has a portion 3a where the conductor portion 3 is exposed from the insulating portion 5 at the longitudinal end portion. It is possible to connect a terminal (not shown) to the portion 3a where the conductor portion 3 is exposed from the insulating portion 5.

[0066] The conductive wire 1 of the sixth embodiment described above also has the same effects as the conductive wire 1 of the first embodiment. Further, the conductive wire 1 of the sixth embodiment can easily provide a portion 3a where the conductor portion 3 is exposed from the insulating portion 5 at the longitudinal end portion. And it is possible to connect a terminal (not shown) to the portion 3a where the conductor portion 3 is exposed from the insulating portion 5 at the longitudinal end portion of the conductive wire 1.

[0067] (Seventh Embodiment) The seventh embodiment will be described with reference to FIGS. 19 and 20. FIG. 19 shows the state before the conductor sheet 2 and the insulating sheet 4 are wound, and FIG. 20 shows a cross section perpendicular to the axis of the completed conductive wire 1. The conductive wire 1 of the seventh embodiment also includes a conductor portion 3 formed by winding the conductor sheet 2, and an insulating portion 5 formed by winding so as to cover the outside of the conductor portion 3 with the insulating sheet 4.

[0068] As shown in FIG. 19, in the seventh embodiment, the insulating sheet 4 is provided so as to overlap with the conductor sheet 2 in the thickness direction at the central portion in the width direction of the surfaces of the conductor sheet 2 facing in the thickness direction. Then, as shown by the arrows R1 and R2 in FIG. 19, the conductive wire 1 is formed by being wound from both ends in the width direction of the conductor sheet 2 toward the central portion in the width direction of the conductor sheet 2 along the direction orthogonal to the longitudinal direction.

[0069] As shown in FIG. 20, the cross-sectional shape of the conductive wire 1 of the seventh embodiment is such that the conductor portion 3 has a shape in which two circles are arranged side by side, and the insulating portion 5 covers the outside thereof.

[0070] The conductive wire 1 of the seventh embodiment described above also exhibits the same operational effects as the conductive wire 1 of the first embodiment.

[0071] (Eighth Embodiment) The eighth embodiment will be described with reference to FIGS. 21 and 22. FIG. 21 shows the state before the conductor sheet 2 and the insulating sheet 4 are wound, and FIG. 22 shows a cross-section perpendicular to the axis of the completed conductive wire 1. The conductive wire 1 of the eighth embodiment also includes a conductor portion 3 formed by winding the conductor sheet 2 and an insulating portion 5 formed by winding the outside of the conductor portion 3 with the insulating sheet 4.

[0072] As shown in FIG. 21, in the eighth embodiment, the insulating sheet 4 is provided side by side on one side in the width direction of the conductor sheet 2. The insulating sheet 4 and the conductor sheet 2 are connected such that the surfaces facing each other in the width direction are in contact with each other. Then, as shown by the arrow R in FIG. 21, the conductive wire 1 is formed by being wound from the side of the conductor sheet 2 opposite to the insulating sheet 4 along the direction orthogonal to the longitudinal direction.

[0073] As shown in FIG. 22, the cross-sectional shape of the conductive wire 1 of the eighth embodiment is substantially the same as the cross-sectional shape of the conductive wire 1 described in the first embodiment.

[0074] The conductive wire 1 of the eighth embodiment described above also exhibits the same operational effects as the conductive wire 1 of the first embodiment.

[0075] (Other embodiments) (1) In the above-described first, second, and fourth to eighth embodiments, the conductive wire 1 is formed by winding the conductor sheet 2 and the insulating sheet 4. However, the present invention is not limited thereto, and in the configurations of those embodiments, as described in the third embodiment, the conductive wire 1 may be formed by folding the conductor sheet 2 and the insulating sheet 4.

[0076] (2) In the above-described third to fifth embodiments, the conductive wire 1 is exemplified as being used as the winding of a coil. However, the present invention is not limited thereto, and the conductive wire 1 may be used for various applications, such as wiring for wired connection between electrical devices.

[0077] (3) In the above-described embodiments, the conductor sheet 2 is made of CNT. However, the present invention is not limited thereto, and for example, pulverized graphite that is formed into a sheet shape and oriented may also be used.

[0078] The present invention is not limited to the above-described embodiments, and can be appropriately modified within the scope described in the claims. Also, the above-described embodiments are not unrelated to each other, and can be appropriately combined except in cases where the combination is clearly impossible. Further, in the above-described embodiments, the elements constituting the embodiments are not necessarily essential except in cases where it is clearly specified as essential and cases where it is considered to be clearly essential in principle. Also, in the above-described embodiments, when numerical values such as the number, numerical value, amount, and range of the constituent elements of the embodiments are mentioned, they are not limited to the specific number except in cases where it is clearly specified as essential and cases where it is clearly limited to a specific number in principle. Also, in the above-described embodiments, when referring to the shape, positional relationship, etc. of the constituent elements, etc., they are not limited to the specific shape, positional relationship, etc. except in cases where it is clearly specified and cases where it is clearly limited to a specific shape, positional relationship, etc. in principle.

Description of reference numerals

[0079] 1 Conductive wire 2 Conductor sheet 3 Conductor part 4 Insulating sheet 5 Insulating portion

Claims

1. In a conductive wire, a conductor part (3) formed in a linear or rod shape in a state where it is wound or folded so that a surface facing the thickness direction of one surface (2b) and the other surface (2c) of a predetermined part (2a) in a sheet-like conductor sheet (2) mainly composed of carbon is in contact with a surface facing the thickness direction of another part (2d, 2e) in the conductor sheet; and an insulating part (5) formed by being wound or folded so as to cover the outside of the conductor part with an insulating sheet (4). The conductive wire comprising the above is provided.

2. The conductive wire according to claim 1, wherein the conductor part is formed in a linear or rod shape in a state where only the conductor sheet is wound or folded along a direction orthogonal to the longitudinal direction of the conductor sheet.

3. The conductive wire according to claim 1, wherein the conductor part is formed in a linear or rod shape in a state where only the conductor sheet is wound or folded along a direction other than the direction orthogonal to the longitudinal direction of the conductor sheet.

4. The conductive wire according to any one of claims 1 to 3, further comprising a metal wire as a core material (6) at the center of the conductor part.

5. The conductive wire according to any one of claims 1 to 3, further comprising a thermoplastic resin member as a core material at the center of the conductor part.

6. The conductive wire according to any one of claims 1 to 3, having a hollow region (7) at the center of the conductor part.

7. The conductive wire according to any one of claims 1 to 6, wherein an end portion in the longitudinal direction of the conductor part is exposed from the insulating part.

8. The conductive wire according to claim 7, further comprising a terminal connected to a part (3a) exposed from the insulating part at an end portion in the longitudinal direction of the conductor part.

9. A method for manufacturing a conductive wire, comprising: a step (S10) of preparing a sheet-like conductor sheet (2) mainly composed of carbon; a step (S20) of preparing the insulating sheet (4) in which the area of the surface facing the thickness direction is smaller than the area of the surface facing the thickness direction in the conductor sheet; a step (S30) of providing the insulating sheet on a part of the conductor sheet. A method for manufacturing a conductive wire, including a step (S40) of forming a linear or rod-shaped conductor part (3) and an insulating part (5) covering the outside of the conductor part by winding or folding the conductor sheet and the insulating sheet from a part of the conductor sheet where the insulating sheet is not provided toward a part of the conductor sheet where the insulating sheet is provided.

10. Before the step of winding or folding the conductor sheet and the insulating sheet, the method further includes a step (S35) of disposing a core material (6) at the center of the conductor part. The method for manufacturing a conductive wire according to claim 9, wherein in the step of winding or folding the conductor sheet and the insulating sheet, the conductor sheet is wound or folded around the core material.

11. The method for manufacturing a conductive wire according to claim 10, further including a step of forming a hollow region (7) at the center of the conductor part by removing the core material disposed at the center of the conductor part after the step of winding or folding the conductor sheet and the insulating sheet.

12. In the step of providing the insulating sheet on a part of the conductor sheet, the insulating sheet is provided so as to exclude the longitudinal ends of the conductor sheet, so that the longitudinal ends of the completed conductive wire are exposed from the insulating part. The method for manufacturing a conductive wire according to any one of claims 9 to 11.

Images