Coating fastener

Abstract

To provide a coating fastener that, in bringing one side and the other side of a predetermined area of a construction electric wire closer to each other, which comprises a core wire and a coating and cutting the construction electric wire therebetween, can prevent the coating from being displaced relative to the core wire.SOLUTION: A coating fastener is used for a construction electric wire cutting method including: a tension alleviation step of, for a construction electric wire comprising a core wire formed of a conductor and a coating formed of a non-conductor and covering the core wire, alleviating a tension acting on a predetermined area of the construction electric wire including a scheduled cutting portion of the construction electric wire by holding one side and the other side of the predetermined area together with the coating to bring both sides relatively closer to each other toward the scheduled cutting portion; and a cutting step of cutting the construction electric wire at the scheduled cutting portion. The coating fastener is attached to a position near the scheduled cutting portion and configured to compress the electric wire from the radial outside to the radial inside to regulate the coating from moving in a direction in which it approaches a processing portion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a covering fastener used when cutting an overhead electric wire having a core wire made of a conductor and a covering made of an insulator that covers the core wire, or when attaching or detaching the electric wire to a support. [Background technology]

[0002] A conventional tool for cutting an overhead electric wire having a core wire and a sheath is a live-line sorting tool described in Patent Document 1. The live-line sorting tool includes a pair of wire grippers that grip both sides of the cutting point in the extension direction of the electric wire from the outside of the sheath, and a pulling tool that pulls the pair of wire grippers in a direction approaching the cutting point.

[0003] In a live line sorting tool configured as described above, the wire gripper can be pulled toward the cutting location, so it is said that the wire can be pulled toward the cutting location and cut in a bent state. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-54021 Summary of the Invention [Problem to be solved by the invention]

[0005] When cutting an overhead electric wire using a live-line distribution tool such as that described in Patent Document 1, the overhead electric wire is cut while the wire gripper is pulled toward the cutting location, so even after the overhead electric wire is cut, the overhead electric wire remains pulled toward the cutting location by the wire gripper. Here, because the wire gripper grips the insulation from the outside, the insulation is pulled toward the cutting location, which can cause the insulation to become misaligned with respect to the core wire.

[0006] Furthermore, the above problem is not limited to when cutting an overhead electric wire, but also occurs when the electric wire is pulled toward a support that supports the electric wire and then detached.

[0007] Therefore, an object of the present invention is to provide a sheathing fastener that can pull specific areas of an overhead electric wire having a core wire and a sheath toward each other, thereby preventing the sheath from shifting relative to the core wire when cutting the overhead electric wire between them or when attaching or detaching the electric wire to a support. [Means for solving the problem]

[0008] The covering fastener of the present invention is a covering fastener used in a method for cutting an overhead electric wire, which includes a tension relief step of gripping one side and the other side of a predetermined region including a planned cutting point where an overhead electric wire having a core wire made of a conductor and a covering made of a non-conductor that covers the core wire is to be cut at a predetermined position in the extension direction, together with the covering, and pulling the predetermined region relatively toward the planned cutting point, thereby releasing the tension acting on the predetermined region, and a cutting step of cutting the overhead electric wire at the planned cutting point in the predetermined region where the tension has been relaxed in the tension relief step, and is configured to be attached to a position near the planned cutting point in the predetermined region by compressing the overhead electric wire from the outer side to the inner side of the diameter, and to restrict the covering from moving relative to the core wire in a direction approaching the planned cutting point.

[0009] According to this configuration, the tension in a predetermined area of ​​the overhead electric wire is relaxed in the tension relaxation process, and the overhead electric wire is cut at the intended cutting point in the cutting process. The overhead electric wire is divided into one side and the other at the cutting point, allowing the coating to move toward the cutting point. Even if a force is applied to the coating in this state to move it toward the cutting point, the coating fastener attached in a compressed state to a position near the intended cutting point prevents the coating from moving in a direction approaching the cutting point, thereby preventing the coating from shifting relative to the core wire.

[0010] The wire may also be configured to include a wire compression surface that contacts the overhead wire from the outside and compresses the overhead wire inward, and a fastening surface that abuts against the coating that is moving toward the intended cutting location from the side of the intended cutting location.

[0011] With this configuration, the wire compression surface abuts against the installed electric wire in a compressive manner, so that the covering fastener is firmly attached to the installed electric wire, and in this state the fastening surface abuts against the covering from the side of the intended cutting point, so that the fastening surface receives the force acting on the covering in the direction approaching the intended cutting point, thereby restricting movement of the covering, thereby preventing the covering from shifting relative to the core wire.

[0012] The covering may also be configured so as to be attachable to the overhead electric wire by compressing it so as to be crushed from the outside diameter to the inside diameter.

[0013] According to this configuration, the sheath fastener is attached to the installed electric wire by compressing the sheath so as to crush it from the outside diameter to the inside diameter, so that the sheath is pressed against the core wire, and the sheath can be securely fastened by the sheath fastener.

[0014] In addition, the method for cutting the installed electric wire includes a step of stripping off at least a portion of the coating from the area including the intended cutting location to form an exposed portion in which the core wire is exposed, and the coating fastener can be configured to be attached to the exposed portion of the core wire so as to compress the core wire from the radially outward direction.

[0015] With this configuration, the covering fastener is attached to the exposed portion of the core wire so as to compress the core wire from the radially outward direction, so that the covering fastener can be reliably fixed to the core wire and can restrict movement of the covering as it approaches the intended cutting point by abutting against the intended cutting point from the side of the intended cutting point, thereby preventing the covering from shifting relative to the core wire.

[0016] Furthermore, the covering fastener of the present invention is a covering fastener used in a method for attaching and detaching an electric wire, which includes a pulling step of grasping an end of an electric wire in the extension direction, including a core wire made of a conductor and a covering made of a non-conductor that covers the core wire, together with the covering, and pulling the end of the electric wire toward the end in the extension direction of the electric wire, and a step of attaching or detaching the end of the electric wire pulled in the pulling step to or from a support that supports the electric wire, and is configured to be attached to the end of the electric wire by compressing the electric wire from the outer side to the inner side of the diameter, and to restrict the covering from moving in a direction approaching the end side in the extension direction of the electric wire relative to the core wire.

[0017] With this configuration, even if a force is applied to the coating that moves toward the end of the wire by pulling the wire, the coating fastener attached to the end of the wire prevents the coating from moving toward the end in the extension direction of the wire, thereby preventing the coating from shifting relative to the core wire.

[0018] The coating may also be configured to be attachable by compressing it onto the wire so as to be crushed from the outside diameter to the inside diameter.

[0019] According to this configuration, the sheath fastener is attached to the wire by compressing the sheath so as to crush it from the outside diameter to the inside diameter, so that the sheath is pressed against the core wire, and the sheath can be securely fastened by the sheath fastener. [Effects of the Invention]

[0020] According to the sheathing fastener of the present invention, it is possible to prevent the sheathing from shifting relative to the core wire when cutting the overhead electric wire between them or when attaching or detaching the electric wire to or from a support by pulling specific areas of the overhead electric wire having a core wire and a sheathing toward each other. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a front view showing a covering fastener according to an embodiment of the present invention. [Figure 2] FIG. [Figure 3] 3A to 3C are diagrams illustrating (1) a bypass line forming step and (2) a pulling tool temporary mounting step in the method for cutting an installed electric wire according to the embodiment. [Figure 4] 10 is a diagram showing the (3) coating fastening step in the method for cutting an installed electric wire. FIG. [Figure 5] FIG. 5 is a cross-sectional view taken along the line V-V in FIG. [Figure 6] 6 is a cross-sectional view showing a state in which the covering fastener is compressed from the state shown in FIG. 5. FIG. [Figure 7] FIG. 7 is a cross-sectional view taken along the line VII-VII shown in FIG. [Figure 8] 10 is a diagram showing the tension relief step (5) in the method for cutting an installed electric wire. FIG. [Figure 9] 6 is a diagram showing the cutting step (6) in the method for cutting the installed electric wire. FIG. [Figure 10] FIG. 10 is a diagram showing the cap attachment step (7) in the method for cutting an installed electric wire. [Figure 11] FIG. 10 is a diagram showing the re-conduction step (10) in the method for cutting an installed electric wire. [Figure 12] FIG. 11 is a diagram showing the insulating cover attaching step (11) in the method for cutting an installed electric wire. [Figure 13] FIG. 10 is a diagram showing the (3) sheath fastening step in the method for cutting an installed electric wire according to the second embodiment of the present invention. [Figure 14] 6 is a diagram showing the cutting step (6) in the method for cutting the installed electric wire. FIG. [Figure 15] 15 is a cross-sectional view taken along the line XV-XV in FIG. 14. [Figure 16] FIG. 10 is a front view showing a covering fastener according to another embodiment of the present invention. [Figure 17] FIG. 10 is a front view showing a covering fastener according to another embodiment of the present invention. [Figure 18] FIG. 10 is a front view showing a covering fastener according to another embodiment of the present invention. [Figure 19] FIG. 10 is a front view showing a covering fastener according to another embodiment of the present invention. [Figure 20]FIG. 10 is a front view showing a covering fastener according to another embodiment of the present invention. [Figure 21] FIG. 10 is a cross-sectional view showing a covering fastener according to another embodiment of the present invention. [Figure 22] FIG. 10 is a cross-sectional view showing a covering fastener according to another embodiment of the present invention. [Figure 23] 1A to 1C are diagrams illustrating a method for attaching and detaching an electric wire according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] A coating fastener 1 and a method for cutting an installed electric wire 2 according to one embodiment of the present invention will be described with reference to Figs. 1 to 12. For convenience of explanation, the vertical direction, depth direction, and width direction will be described based on the directions shown in Figs. 1 and 2.

[0023] First, the covering fastener 1 will be described with reference to FIGS.

[0024] As shown in FIG. 1 , the sheathing fastener 1 includes a first compression portion 11 that forms one longitudinal end portion, a second compression portion 12 that is disposed opposite the other longitudinal side of the first compression portion 11, and a connecting portion 13 that connects the first compression portion 11 and the second compression portion 12. The sheathing fastener 1 is a generally C-shaped plate-like body that has a predetermined length in the width direction and an end face that extends in a planar direction perpendicular to the width direction. The sheathing fastener 1 is also made entirely of metal. The sheathing fastener 1 of this embodiment is made of the same type of metal as the core wire 21 of the overhead electric wire 2.

[0025] The first compression section 11 is a plate-like body curved so as to convex outward (to one longitudinal side) in the direction facing the second compression section 12, and has an inner surface that is the surface on the other longitudinal side and an outer surface that is the surface on one longitudinal side. Both the inner and outer surfaces of the first compression section 11 are curved so as to convex toward one longitudinal side. The first compression section 11 includes a compression end 14 that forms the front end, a compression main body 15 that forms the middle portion in the depth direction, and a compression connecting portion 16 that forms the rear end. The compression end 14 has a compression end surface 14a that extends from the inner surface to the outer surface of the first compression section 11. The compression end surface 14a is a curved surface without any corners.

[0026] The compression body 15 is a plate-like body with a substantially constant thickness (the distance from the inner surface to the outer surface) and extends from the compression end 14 to the compression connecting portion 16. The inner and outer surfaces of the compression body 15 are curved and convex on one side in the vertical direction, and the inner and outer surfaces are smooth and free of protrusions. The outer surface of the compression body 15 is the tool contact surface 1a that contacts the jaws of the compression tool 9, which will be described later.

[0027] The compression connecting portion 16 is located on the near side of the compression body portion 15 in the depth direction and extends from the compression body portion 15 toward the other side in the vertical direction. Specifically, the compression connecting portion 16 is a curved portion that extends from the other end of the compression body portion 15 toward the other side in the vertical direction and toward the far side in the depth direction. Furthermore, the compression connecting portion 16 extends further toward the other side in the vertical direction than the compression end portion 14.

[0028] The second compression section 12 has a shape symmetrical in the vertical direction to the first compression section 11. Specifically, the second compression section 12 includes a compression end section 14 constituting the front end section, a compression connecting section 16 constituting the rear end section, and a compression main body section 15 constituting the middle section in the depth direction.

[0029] The connecting portion 13 is a plate-like body having one vertical end connected to the compression connecting portion 16 of the first compression portion 11 and the other vertical end connected to the compression connecting portion 16 of the second compression portion 12, connecting the first compression portion 11 and the second compression portion 12. The connecting portion 13 is a plate-like body extending linearly along the vertical direction, and has a straight inner surface located on the front side and extending along the vertical direction, and a straight outer surface located on the back side and extending along the vertical direction. The connecting portion 13 has a substantially constant thickness, which is the distance between the inner surface and the outer surface, and the inner and outer surfaces of the connecting portion 13 are flat surfaces without protrusions.

[0030] The inner surfaces of the first compression portion 11, the second compression portion 12, and the connecting portion 13 constitute the wire compression surface 1b, which is the inner surface of the sheathing fastener 1. The wire compression surface 1b is a substantially C-shaped surface when viewed from one side in the width direction. Specifically, one end and the other end in the longitudinal direction are curved and convex outward, and the other end in the longitudinal direction are a surface that extends straight. The inner surfaces of the first compression portion 11, the second compression portion 12, and the connecting portion 13 are connected to each other so as to extend continuously, and the wire compression surface 1b is a smooth surface without any protrusions protruding inward. The sheathing fastener 1 also forms a wire accommodation region 1c surrounded by the wire compression surface 1b. Furthermore, an opening 1d is formed between the compressed end 14 of the first compression portion 11 and the compressed end 14 of the second compression portion 12, and the opening 1d is configured to connect the inside and outside of the wire accommodation region 1c. In other words, the sheathing fastener 1 is formed in an annular shape, and the interior of the annular shape constitutes the wire accommodation region 1c. The covering fastener 1 is also open midway through the annular shape, forming a compressed end portion 14 of the first compressed portion 11 and a compressed end portion 14 of the second compressed portion 12. Furthermore, the compressed end portion 14 of the first compressed portion 11 and the compressed end portion 14 of the second compressed portion 12 face each other at a distance in the circumferential direction of the annular shape, thereby forming an opening 1d between the compressed end portions 14.

[0031] As shown in FIGS. 1 and 2 , both widthwise end surfaces of the first compression portion 11, the second compression portion 12, and the connecting portion 13 constitute a fastening surface 1e, which extends in the vertical and depth directions. The fastening surface 1e is a substantially C-shaped surface when viewed from one side in the width direction. Specifically, one end and the other end in the vertical direction are curved and convex outward, and the one end and the other end in the vertical direction extend straight. The end surfaces in the width direction of the first compression portion 11, the second compression portion 12, and the connecting portion 13 are connected to each other so as to extend continuously without any steps. The fastening surface 1e is connected to the widthwise end of the wire compression surface 1b via a corner 17. The fastening surface 1e and the wire compression surface 1b are surfaces that extend in substantially perpendicular directions, and the corner 17 is a ridge formed by the intersection of the fastening surface 1e and the wire compression surface 1b. The corner 17 is a sharp corner that is not chamfered and is approximately 90 degrees in this embodiment.

[0032] The covering fastener 1 has a longer vertical length than a longer depth length. The covering fastener 1 has a shorter width than the vertical and depth lengths. Furthermore, the thickness of the covering fastener 1 is approximately constant.

[0033] As shown in FIG. 5 , the opening 1d of the covering fastener 1 is wider than the outer diameter of the overhead electric wire 2. Specifically, the distance between the pair of compressed ends 14 of the covering fastener 1 is longer than the outer diameter of the overhead electric wire 2 but smaller than twice the outer diameter of the overhead electric wire 2. Furthermore, the depth and vertical lengths of the wire accommodation area 1c are longer than the outer diameter of the overhead electric wire 2 but smaller than twice the outer diameter of the overhead electric wire 2. In other words, the wire accommodation area 1c can accommodate one overhead electric wire 2 but cannot accommodate two or more overhead electric wires 2. Furthermore, the covering fastener 1 is compressed at a single location in the center in the width direction, and in this embodiment, the entire width direction is compressed. Furthermore, the thickness of the covering fastener 1 is approximately the same as or thicker than the thickness of the covering 22 of the overhead electric wire 2.

[0034] Next, a method for cutting the installed electric wire 2, which is an installed electric wire, will be described with reference to Fig. 3 to Fig. 12. The installed electric wire 2 is cut, for example, for the purpose of cutting a part of the electric wire for main construction work.

[0035] First, the overhead electric wire 2 to be cut by the cutting method for the overhead electric wire 2 will be described. As shown in FIG. 5 , the overhead electric wire 2 includes a core wire 21 made of a conductor and a covering 22 made of an insulator and arranged to cover the outer surface of the core wire 21. The core wire 21 is formed by combining a plurality of strands 211 made of conductors thinner than the core wire 21. The overhead electric wire 2 of this embodiment has a radial cross section of approximately 200 square millimeters, the core wire 21 is an aluminum electric wire, the core wire diameter is approximately 17 mm, the covering thickness is approximately 3 mm, and the overall diameter is approximately 23 mm. The overhead electric wire 2 of this embodiment is a distribution line used to carry a high voltage current of 6.6 kV. The overhead electric wire 2 is installed on a pair of supports (not shown), such as utility poles, and is under tension due to the weight of the overhead electric wire 2 itself, etc. In the method for cutting the installed electric wire 2 of this embodiment, the installed electric wire 2 is cut at a span that is a midpoint between the supports.

[0036] In the method for cutting an overhead electric wire 2 of this embodiment, the overhead electric wire 2 is cut at a tensioned portion, then main construction is performed, and then electrical continuity is restored between the cut overhead electric wires 2. Specifically, the method for cutting an overhead electric wire 2 of this embodiment includes (1) a bypass line forming step, (2) a laying tool temporary attachment step, (3) a covering fastening step, (4) a laying tool main attachment step, (5) a tension relieving step, (6) a cutting step, (7) a cap attachment step, (8) a main construction step, (9) a cut portion skin stripping step, (10) a reconnection step, (11) an insulating cover attachment step, and (12) a laying tool removal step.

[0037] (1) Bypass line construction process As shown in FIG. 3 , (1) the bypass line forming step is a step of forming a line that bypasses the planned cutting point C of the overhead electric wire 2. Specifically, a bypass line 3 is formed that connects a position away from the planned cutting point C on one side and a position away from the planned cutting point C on the other side in the extension direction of the overhead electric wire 2. The bypass line 3 includes a cord-like bypass line 31, a construction switch 32 disposed midway along the bypass line 31, and bypass attachment units 33 disposed at both ends of the bypass line 31 and attached to the overhead electric wire 2. The construction switch 32 is installed, for example, on a nearby utility pole. In the bypass line forming step, the covering 22 of the overhead electric wire 2 is stripped at positions away from the planned cutting point C on one side and the other side of the overhead electric wire 2 to expose the core wire 21, and the bypass attachment units 33 are attached to the exposed portion, thereby electrically connecting one side of the planned cutting point C to the other side via the bypass line 31. When a power outage is required for the bypass line 3, the construction switch 32 is set to the open state, and when a power outage is not required, the construction switch 32 is set to the closed state.

[0038] (2) Temporary attachment process of the pull-up tool As shown in Fig. 3, (2) the process of temporarily attaching the laying tool is a process of temporarily attaching the laying tool 4 to the installed electric wire 2. The laying tool 4 includes a pair of wire grippers 41 and a laying section 42 located between the pair of wire grippers 41.

[0039] The wire gripper 41 grips the installed electric wire 2 from outside the sheath 22 and restricts the installed electric wire 2 from moving relative to the wire gripper 41 in the direction opposite to the pulling-in direction. Specifically, the wire gripper 41 includes a receiving portion 43 through which the installed electric wire 2 is inserted, a wire gripping connecting portion 44 connected to the pulling-in portion 42, and a cam portion 45 disposed between the receiving portion 43 and the wire gripping connecting portion 44. When the wire gripping connecting portion 44 is pulled in the pulling-in direction, the tensile force is converted by the cam portion 45 into a force in a direction that closes the receiving portion 43, and the inserted installed electric wire 2 can be gripped by the closing of the receiving portion 43. When the wire gripping connecting portion 44 is pushed in the direction opposite to the pulling-in direction, the receiving portion 43 opens via the cam portion 45. The pair of wire grippers 41 are each disposed so that the wire gripping connecting portion 44 is located on the side of the intended cutting location C.

[0040] The clamping portion 42 includes a rod-shaped insulating rod portion 46 made of an insulator, a rod-shaped expandable portion 47 connected to the insulating rod portion 46, and a mounting auxiliary portion 48. The insulating rod portion 46 is a rod-shaped body having a length sufficient to electrically insulate one side of the insulating rod portion 46 from the other, and is made of, for example, fiber-reinforced plastic. The expandable portion 47 includes an expandable main body portion 471 connected to one end of the insulating rod portion 46 in the extension direction and extending along the extension direction of the insulating rod portion 46, and an expansion / contraction operating portion 472 for expanding and contracting the expandable main body portion 471. The expandable portion 47 is configured such that, for example, the expandable main body portion 471 expands and contracts by rotating the expansion / contraction operating portion 472. The mounting auxiliary portion 48 is an annular body provided on one side and the other side of the insulating rod portion 46. The inner diameter of the mounting auxiliary portion 48 is larger than the outer diameter of the insulating cover 8 (described later), and a portion of the circumferential direction is configured to be openable and closable. The attachment auxiliary portion 48 has the overhead electric wire 2 inserted therethrough, and when, for example, the wire gripper 41 falls off the overhead electric wire 2, it engages with the overhead electric wire 2, thereby preventing the entire pulling tool 4 from falling.

[0041] In the laying tool temporary attachment step, one of the wire grippers 41 and the attachment auxiliary part 48 of the laying tool 4 is attached to the installed electric wire 2, and the laying tool 4 is temporarily attached to the installed electric wire 2. Specifically, in the laying tool temporary attachment step, one of the wire grippers 41 is attached to a support (e.g., a utility pole) supporting the installed electric wire 2 at a position where the distance required for connecting the bypass line 3 is provided and where the planned cutting point C is included between the pair of wire grippers 41. In the laying tool temporary attachment step of this embodiment, one end of a distance ensuring member for providing the distance required for connecting the bypass line 3 to the support supporting the installed electric wire 2 is placed against the support, which is the starting point for providing the distance, and is aligned along the installed electric wire 2. The other end of the distance ensuring member then becomes the attachment position of the one of the wire grippers 41. The distance ensuring member of this embodiment is an insulating cover 8, and, for example, one of the wire grippers 41 is attached to a support supporting the installed electric wire 2 at a distance equivalent to one insulating cover 8, which will be described later.

[0042] (3) Covering process As shown in FIGS. 4 to 7 , (3) the sheath fastening step is a step of attaching the sheath fastener 1 to the vicinity of the planned cutting location C of the overhead electric wire 2. In the sheath fastening step, the sheath fastener 1 is attached between the planned cutting location C and the position where the wire gripping tool 41 is attached so that the width direction of the sheath fastener 1 coincides with the extension direction of the overhead electric wire 2. In the sheath fastening step of this embodiment, the sheath fastener 1 is attached to positions on both one side and the other side of the planned cutting location C of the overhead electric wire 2. Specifically, the sheath fastener 1 is moved so that the opening 1d faces the overhead electric wire 2 and the depth direction of the sheath fastener 1 is aligned with the radial direction of the overhead electric wire 2 so as to approach the overhead electric wire 2. In the sheath fastening step of this embodiment, the sheath fastener 1 is attached from the radial outside of the sheath 22.

[0043] In the sheathing fastening process, a position for attaching the sheathing fastener 1 to the installed electric wire 2 is determined using a guide member 5 that serves as a guide for the position for attaching the sheathing fastener 1 (see FIG. 12 ). In this embodiment, the guide member 5 is an insulating cover 8, and the position for attaching the sheathing fastener 1 to the installed electric wire 2 is determined by referring to guide indicators 51 displayed on the outer surface of the insulating cover 8. The insulating cover 8 serving as the guide member 5 has lines formed thereon as guide indicators 51 at positions offset to one side and the other side from the center in the extension direction. Using such a guide member 5, for example, the insulating cover 8 is placed on the installed electric wire 2 so that the planned cutting location C is located at the center in the extension direction of the insulating cover 8 serving as the guide member 5, and the positions corresponding to the guide indicators 51 on one side and the other side can be determined as the positions for attaching the sheathing fastener 1. Alternatively, the insulating cover 8 serving as the guide member 5 may be configured without the guide indicators 51 displayed thereon. Even in the case of such a configuration, the insulating cover 8 is placed on the installed electric wire 2 so that approximately the center of the insulating cover 8 coincides with the intended cutting point C, and the position within the range where the insulating cover 8 is located on one side of the intended cutting point C and the position within the range where the insulating cover 8 is located on the other side of the intended cutting point C can be determined as the positions to attach the covering fastener 1.

[0044] In addition, for example, the attachment position of one of the sheathing fasteners 1 can be determined using a wire gripping distance guide member that serves as a guide for the distance from one of the wire grippers 41. The sheathing fastener 1 on one side can be attached to a position on the other side from the position where the one of the wire grippers 41 was attached in the temporary attachment process, which is the distance of one insulating cover 8 as a wire gripping distance guide member, and the guide display portion 51 on one side of the guide member 5 can be placed at the position where the one of the sheathing fasteners 1 is attached, and the position where the guide display portion 51 on the other side is located can be used to attach the other sheathing fastener 1. In this case, the planned cutting point C is located midway between the positions where the one of the sheathing fasteners 1 is attached and the other of the sheathing fasteners 1 is attached. Furthermore, the sheathing fastener 1 can be approached from below and from the rear side relative to the installed electric wire 2 with the opening of the crimping tool 9 and the opening 1d of the sheathing fastener 1 facing upward. In this method, the covering fastener 1 can be attached to the installed electric wire 2 while being held from below by the compression tool 9, thereby preventing the covering fastener 1 from falling off the compression tool 9. In addition, the opening of the compression tool 9 faces upward and toward the front, making it easy to work while visually checking the covering fastener 1.

[0045] As shown in FIG. 5 , in the sheathing fastening process, a sheathing fastener 1 is attached to an installed electric wire 2 using a compression tool 9. The compression tool 9 includes an upper jaw 9U and a lower jaw 9D. The upper jaw 9U and the lower jaw 9D approach each other to compress an object to be compressed housed between the upper jaw 9U and the lower jaw 9D. In the sheathing fastening process, the sheathing fastener 1 as an object to be compressed is housed and compressed between the upper jaw 9U and the lower jaw 9D. Specifically, the sheathing fastener 1 is placed on the compression tool 9 so that the tool contact surface 1a of the first compression portion 11 faces the upper jaw 9U and the tool contact surface 1a of the second compression portion 12 faces the lower jaw 9D. Then, with the sheathing fastener 1 placed in the compression tool 9, the installed electric wire 2 is inserted into the electric wire receiving area 1c through the opening 1d. Since the compression end surface 14a has no corners, damage to the installed electric wire 2 by the compression end surface 14a can be prevented. In this state, there is a gap between the outer surface of the installed electric wire 2 (the outer surface of the coating 22) and the wire compression surface 1b. With the installed electric wire 2 accommodated in the wire accommodation area 1c in this manner, the coating fastener 1 is compressed. The compression tool 9 compresses one location in the widthwise center of the coating fastener 1, and in this embodiment, compressing one location compresses the entire widthwise area.

[0046] As shown in FIG. 6 , when the sheathing fastener 1 is compressed, the first compression portion 11 and the second compression portion 12 approach each other, and the compressed ends 14 of the first compression portion 11 and the second compression portion 12 approach each other, causing the opening 1d to deform and become narrower. Furthermore, as the first compression portion 11 and the second compression portion 12 approach each other, the wire accommodation area 1c narrows, and the wire compression surface 1b compresses the sheath 22 radially inward. Specifically, as the first compression portion 11 and the second compression portion 12 approach each other, the straight-shaped connecting portion 13 of the sheathing fastener 1 curves and deforms so that its outer surface is convex, causing the wire compression surface 1b to deform and conform to the outer surface of the installed electric wire 2. At this time, the inner diameter of the wire compression surface 1b becomes smaller than the outer diameter of the sheath 22, causing the wire compression surface 1b to compress the sheath 22 radially inward. When the sheathing fastener 1 is compressed, a portion of the wire compression surface 1b comes into contact with the core wire 21. Specifically, the inner surface of the compressed end portion 14 crushes and breaks the coating 22, causing a portion of the wire compression surface 1b to come into contact with the core wire 21. The crushed coating 22 is located between the core wire 21 and the wire compression surface 1b in at least half of the circumferential area of ​​the installed electric wire 2. This prevents direct contact between the wire compression surface 1b and the core wire 21, thereby preventing damage to the core wire 21. Even when the coating fastener 1 is compressed, the compressed end portions 14 of the first compression portion 11 and the second compression portion 12 do not abut against each other, and a gap is formed between the compressed end portions 14. This prevents further compression from occurring after the compressed end portions 14 abut against each other, causing the compressed end portions 14 to deform radially inward, thereby preventing damage to the core wire 21. In this way, the coating fastener 1 is attached to the installed electric wire 2 so as to crush the coating 22 of the installed electric wire 2, thereby firmly attaching the coating fastener 1 to the installed electric wire 2. Specifically, the covering fastener 1 is attached to the installed electric wire 2 strongly enough that it will not move in the extension direction of the installed electric wire 2 even when subjected to a pulling force described below. In this embodiment, the wire compression surface 1b comes into contact with the core wire 21, so that the covering fastener 1 can be prevented from moving in the extension direction of the installed electric wire 2 relative to the core wire 21. Note that the covering fastener 1 of this embodiment slightly compresses the core wire 21 at the portion in contact with the core wire 21 (to an extent that does not affect the durability of the core wire 21).

[0047] As shown in FIG. 7, the crushed coating 22 has a reduced thickness and an outer diameter smaller than that of the uncrushed portion. In other words, the coating fastener 1 crushes the coating 22 by strongly pressing the coating 22 from the radially outer side to the radially inner side, thereby deforming the coating 22 to reduce its thickness. The crushed portion of the coating 22 has a reduced thickness, for example, because the thickness is reduced by compression or because a portion of the coating escapes to the adjacent portion 2A. Furthermore, the crushed coating 22 is partially broken by compression, forming a portion in the circumferential direction of the installed electric wire 2 where the core wire 21 is not covered by the coating 22. The wire compression surface 1b comes into contact with the portion of the core wire 21 that is not covered by the coating 22.

[0048] Here, the wire compressing surface 1b of the covering fastener 1 is a smooth surface without protrusions, so that the portion in contact with the outer surface of the covering 22 can be entirely crushed. This prevents the covering 22 from being entirely broken when crushed by the wire compressing surface 1b. Furthermore, because the wire compressing surface 1b is a smooth surface, it entirely crushes the portion in contact with the core wire 21, so that it is possible to prevent the core wire 21 from being broken by a localized compressive force being applied to the core wire 21. Furthermore, sharp corners 17 are formed on both ends in the width direction of the wire compressing surface 1b, so that both ends of the wire compressing surface 1b can firmly bite into the installed wire 2. This allows the wire compressing surface 1b to reliably compress and crush the covering 22 of the installed wire 2. Furthermore, because the width direction length of the wire compressing surface 1b is smaller than the vertical direction length and the depth direction length, the compressive force can be efficiently applied to the portion of the covering 22 in contact with the wire compressing surface 1b. Therefore, the sheath 22 of the installed electric wire 2 can be reliably compressed and crushed by the electric wire compressing surface 1b.

[0049] As shown in FIG. 7 , when the sheathing fastener 1 is attached to the installed electric wire 2, the fastening surface 1e of the sheathing fastener 1 and the adjacent portion 2A of the sheathing 22 adjacent to the fastening surface 1e face each other in the extension direction of the installed electric wire 2. Specifically, the thick portion 221 of the sheathing 22 in the adjacent portion 2A faces the fastening surface 1e in the extension direction of the installed electric wire 2, and the thick portion 221 of the adjacent portion 2A can abut against the fastening surface 1e. Furthermore, because the corners 17 are sharp, even if the adjacent portion 2A is pulled toward the sheathing fastener 1, the sheathing 22 can be prevented from slipping inside the sheathing fastener 1. Furthermore, because the force tending to displace the sheathing 22 can be received by the wire compressing surface 1b and the fastening surface 1e, which are perpendicular surfaces, the force tending to displace the sheathing 22 can be prevented from acting in a direction that opens the sheathing fastener 1, and the sheathing fastener 1 is less likely to loosen. Furthermore, since the covering fastener 1 is in contact with the core wire 21, even if the covering 22 as a whole tries to move in the extension direction of the overhead electric wire 2, the covering fastener 1 can be prevented from shifting relative to the core wire 21, and therefore the covering 22 can be prevented from shifting relative to the core wire 21.

[0050] (4) Pulling tool installation process As shown in FIG. 8 , (4) the laying tool permanent attachment step is a step of attaching the laying tool 4 to the laid electric wire 2. In the laying tool permanent attachment step of this embodiment, the other wire gripper 41 and the attachment auxiliary part 48 are attached to the laid electric wire 2. Specifically, in the laying tool permanent attachment step, the wire gripper 41 is positioned so that both the planned cutting location C and the insulation fastener 1 attached to the laid electric wire 2 are included between the one wire gripper 41 and the other wire gripper 41, and the laying tool 4 is attached to the laid electric wire 2. For example, if the position of the one wire gripper 41 temporarily attached in the (2) laying tool temporary attachment step is not appropriate, the position of the one wire gripper 41 is adjusted, and then the other wire gripper 41 and the attachment auxiliary part 48 are attached to the laid electric wire 2. Furthermore, if the position of one of the wire grippers 41 temporarily attached in the (2) temporary attachment step of the pulling-in tool is appropriate, the other wire gripper 41 is attached to the installed wire 2 without moving the one wire gripper 41 relative to the installed wire 2. When the permanent attachment step of the pulling-in tool is completed and the pulling tool 4 is attached, the insulation fastener 1 and the planned cutting point C are located between the pair of wire grippers 41, and the planned cutting point C is located between both of the insulation fasteners 1. Furthermore, if there is a location where the insulation 22 has been stripped to electrically connect to another installed wire 2 at a position on the opposite side of the planned cutting point C from the position where the insulation fastener 1 is attached to the installed wire 2, for example, the distance from the stripped location to the insulation fastener 1 is preferably 1000 mm or more, and more preferably 1200 mm or more. With this configuration, when the sheath 22 tries to slip, it is more likely to receive resistance from the core wire 21, and this, combined with the effect of the sheath fastener 1, can prevent the sheath 22 from slipping relative to the core wire 21. It is also preferable that the sheath 22 extend continuously from the position where the wire gripper 41 is attached to the sheath fastener 1. With this configuration, it is possible to reliably prevent the sheath 22 from slipping.

[0051] (5)Tension relaxation process As shown in FIG. 8 , (5) tension relief step is a step of relieving the tension applied to the installed electric wire 2 by pulling in the installed electric wire 2 between one wire gripper 41 and the other wire gripper 41. Specifically, in the tension relief step, the drawing-in portion 42 is contracted to draw in the one wire gripper 41 and the other wire gripper 41 in a direction toward each other, thereby drawing in the installed electric wire 2 gripped by both wire grippers 41, thereby relieving the tension applied to the installed electric wire 2, and a portion of the tension applied to the installed electric wire 2 is applied to the drawing tool 4. In the tension relief step of this embodiment, the extension / retraction main body portion 471 is contracted by operating the extension / retraction operating portion 472 of the extension / retraction portion 47, thereby drawing in the one wire gripper 41 and the other wire gripper 41 in a direction toward each other. In this way, the tension between one wire gripping device 41 and the other wire gripping device 41 on the overhead electric wire 2 is relaxed in the tension relaxation process, thereby relaxing the tension applied to a predetermined area including the planned cutting point C and the location where the insulation fastener 1 is attached. Furthermore, the wire gripping devices 41 are pulled toward each other, so a force is applied to the insulation 22 of the overhead electric wire 2 gripped by the wire gripping device 41 to move in the pulling direction. The tension relaxation process is completed when the tension applied to the overhead electric wire 2 is relaxed at least to an extent that does not interfere with the cutting of the planned cutting point C. In other words, in the tension relaxation process, the overhead electric wire 2 is either in a state where some tension remains on the overhead electric wire 2, or in a state where no tension is applied at all, or in a state where the overhead electric wire 2 is compressed in the extension direction to an extent that does not interfere with the cutting of the planned cutting point C.

[0052] (6) Cutting process As shown in FIG. 9, (6) cutting step is a step of cutting the intended cutting location C using a tool, and cutting the installed electric wire 2 at a position between both of the covering fasteners 1 arranged at a distance in the extension direction of the installed electric wire 2. In the cutting step, for example, the installed electric wire 2 is cut using a blade as a tip tool provided at the tip of an insulating work rod made of an insulator. In the cutting step, both the covering 22 and the core wire 21 are cut.

[0053] Even after the cutting is complete, the installed electric wire 2 is still pulled by the pulling tool 4, so the portion of the installed electric wire 2 gripped by the wire gripper 41 is pulled toward the cutting location. Therefore, a force is applied to the sheath 22 along the outer surface of the core wire 21 in a direction that moves the sheath 22 toward the cutting location. However, as shown in FIG. 8 , the sheath fastener 1 is attached between the wire gripper 41 and the cutting location. Therefore, when the sheath 22 attempts to move toward the cutting location, the adjacent portion 2A abuts against the fastening surface 1e, restricting the sheath 22 from moving relative to the core wire 21. Therefore, the sheath 22 is prevented from shifting relative to the core wire 21. Furthermore, as shown in FIG. 7 , the sheath fastener 1 presses the sheath 22 against the core wire 21, so the sheath 22 is prevented from shifting relative to the core wire 21. Furthermore, the sheath fastener 1 is in contact with the core wire 21, so the sheath fastener 1 is prevented from shifting relative to the core wire 21. Therefore, even if the entire coating 22 attempts to move in the extension direction of the installed electric wire 2, the coating 22 can be prevented from shifting relative to the core wire 21 by abutting against the fastening surface 1e.

[0054] (7) Cap attachment process As shown in FIG. 10 , the capping step (7) is a step of attaching an insulating cap 6 to the cut portion 2B of the overhead electric wire 2. The cap 6 is an insulating tubular body with a closed tip. In the capping step, the cut portion 2B of the overhead electric wire 2 and the covering fastener 1 attached to the overhead electric wire 2 are both covered and insulated with the cap 6. This step can prevent accidents such as short circuits and ground faults that may occur when the cut overhead electric wire 2 comes into contact with another overhead electric wire 2, etc. Furthermore, since the cap 6 is attached to cover the covering fastener 1, even if the covering fastener 1 crushes the covering 22 and the portion where the covering fastener 1 is attached becomes insufficiently insulated, the cap 6 provides insulation, thereby preventing accidents such as short circuits and ground faults.

[0055] (8) Main construction process (8) This work process is a process for performing work that requires power outage of the erected electric wire 2, such as replacing utility poles or equipment. This work process may be performed immediately after (7) Cap Attachment Process, or may be performed after an interval of several days or weeks, for example. The pulling tool 4 may be removed from the erected electric wire 2 after (7) Cap Attachment Process, or this work process may be performed with the pulling tool 4 attached. If the pulling tool 4 is removed in this work process, the pulling tool 4 is reattached to the erected electric wire 2 before (9) Cutting Portion Stripping Process, and the expandable portion 47 is contracted to relieve the tension on the portion including the cut portion 2B.

[0056] (9) Cutting section peeling process As shown in FIG. 11 , the (9) cut portion stripping step is a step of stripping the sheath 22 near the cut portion of the overhead electric wire 2 to expose the core wire 21. Specifically, in the cut portion stripping step, the cap 6 is removed, and all or part of the sheath 22 from the cut portion to the sheath fastener 1 is stripped off to an extent necessary to establish electrical continuity between one side of the cut portion and the other side in the (10) re-conduction step. In the cut portion stripping step of this embodiment, the distance between the sheath fasteners 1 is set to the distance necessary for re-conduction, so the sheath 22 between the cut portion and the sheath fastener 1 is stripped off. However, this is not limited to this case, and the sheath 22 can also be stripped from the cut portion to just before the sheath fastener 1. Various tools can be used to strip the sheath 22 from the cut portion 2B. When the cut portion stripping step is completed, the core wire 21 on the cut portion side of the sheath fastener 1 is exposed.

[0057] (10) Reconduction process As shown in FIG. 11 , the (10) re-conduction step is a step of electrically connecting the core wires 21 on one side and the other side of the cut portion to each other, thereby restoring electrical continuity between the one side and the other side of the cut portion. In the re-conduction step, a cylindrical connector 7 made of a conductor is used to electrically connect the core wires 21 on one side and the other side of the cut portion to each other. The connector 7 in this embodiment is a straight sleeve. Specifically, in the re-conduction step, the core wire 21 on one side of the cut portion is inserted from one end of the connector 7 toward the other end, and the connector 7 is compressed at multiple locations from the radially outer side to the radially inner side, thereby crimping the core wire 21 on one side of the cut portion to the connector 7 at multiple locations. Next, the core wire 21 on the other side of the cut portion is inserted from the other end of the connector 7 toward the other end, and the connector 7 is compressed at multiple locations from the radially outer side to the radially inner side, thereby crimping the core wire 21 on the other side of the cut portion to the connector 7 at multiple locations. By this step, the installed electric wires 2 on one side and the other side of the cut portion are connected by the connector 7 and are brought into an electrically conductive state.

[0058] It should be noted that the (9) Cutting Portion Stripping Step and the (10) Reconnection Step are not limited to being performed simultaneously on one side and the other side of the cut portion. For example, the (9) Cutting Portion Stripping Step and the (10) Reconnection Step can be performed on one side of the cut portion, and then, with the one side of the cut portion and the connector 7 crimped, the (9) Cutting Portion Stripping Step and the (10) Reconnection Step can be performed on the other side of the connection portion.

[0059] (11) Insulation cover installation process As shown in FIG. 12 , (11) the insulating cover attaching step is a step of attaching an insulating cover 8 to cover the connector 7. The insulating cover 8 is a cylindrical body made of an insulator and is configured to be placed over the connector 7 to insulate the outer surface of the connector 7. In this embodiment, the insulating cover 8 is a guide member 5, and guide markings 51 are provided on the insulating cover 8. In the insulating cover attaching step, the insulating cover 8 is attached to the connector 7 and the nearby overhead electric wire 2 so that the center of the insulating cover 8 corresponds to the center of the connector 7. At this time, the covering fastener 1 is positioned at a position corresponding to the guide markings 51 on the insulating cover 8. In other words, in the insulating cover attaching step, the insulating cover 8 covers and insulates the connector 7 and the covering fastener 1. This step can prevent short circuits and ground faults that may occur when the connector 7 comes into contact with another overhead electric wire 2, etc. Furthermore, because the insulating cover 8 is attached to cover the sheathing fastener 1, even if the sheathing fastener 1 is in direct contact with the core wire 21, or even if the sheathing fastener 1 is not in direct contact with the core wire 21 but crushes the sheathing 22, causing insufficient insulation at the location where the sheathing fastener 1 is attached, accidents such as short circuits and ground faults caused by other overhead electric wires 2 coming into contact with the sheathing fastener 1 can be suppressed. Note that in a configuration in which the guide display portion 51 is not displayed on the insulating cover 8 serving as the guide member 5, even if the positions at which the sheathing fastener 1 is attached are determined to be within a range where the insulating cover 8 is located on one side of the planned cutting point C and a range where the insulating cover 8 is located on the other side of the planned cutting point C, the sheathing fastener 1 can be reliably covered with the insulating cover 8. Therefore, accidents such as short circuits and ground faults caused by the sheathing fastener 1 coming into contact with other overhead electric wires 2 can be suppressed.

[0060] (12) Pulling tool removal process (12) The laying tool removal process is a process of removing the laying tool 4 attached to the laid electric wire 2. In the laying tool removal process, the tension applied to the laying tool 4 is returned to the laid electric wire 2, and the laying tool 4 is removed after the tension is no longer applied to the laid electric wire 2. Specifically, by operating the extension operating part 472 of the extension part 47 and extending the extension main body part 471, the tension applied to the laying tool 4 is gradually returned to the laid electric wire 2, and the laying tool 4 is no longer applied with tension, and then the wire gripping device 41 and the attachment auxiliary part 48 are removed from the laid electric wire 2, and the laying tool 4 attached to the laid electric wire 2 is removed.

[0061] Note that the tension is not limited to being returned to the laid electric wire 2 in the (12) laying tool removal step, but may also be returned to the laid electric wire 2, for example, between the (10) re-conduction step and the (11) insulating cover attachment step. In such a configuration, tension is applied to the laid electric wire 2, and the insulating cover 8 is attached in a state in which the laid electric wire 2 is taut, making it easy to attach the insulating cover 8. In addition, the tension can be returned to the laid electric wire 2 between the (10) re-conduction step and the (11) insulating cover attachment step, and the laying tool 4 can be removed from the laid electric wire 2. In such a configuration, interference with the laying tool 4 when attaching the insulating cover 8 can be suppressed, making it easy to attach the insulating cover 8.

[0062] With the above steps, the cutting of the overhead electric wire 2 is completed.

[0063] According to the covering fastener 1 described above, the tension in a predetermined area of ​​the overhead electric wire 2 is relaxed in the tension relaxation process, and the overhead electric wire 2 is cut at the intended cutting point C in the cutting process, and the overhead electric wire 2 is divided into one side and the other at the cutting point, allowing the covering 22 to move toward the cutting point. Even if a force is applied to the covering in this state to move it toward the cutting point, the covering fastener 1, which is compressed and attached at a position near the intended cutting point C, prevents the covering from moving in a direction approaching the cutting point, and therefore, the covering 22 can be prevented from shifting relative to the core wire 21.

[0064] Furthermore, since the wire compressing surface 1b abuts against the installed electric wire 2 in a compressive manner, the covering fastener 1 is firmly attached to the installed electric wire 2, and in this state the fastening surface 1e abuts against the covering 22 from the side of the intended cutting point C, so that the fastening surface 1e receives the force acting on the covering 22 in the direction approaching the intended cutting point C, thereby restricting movement of the covering 22. Therefore, the covering 22 can be prevented from shifting relative to the core wire 21.

[0065] Since the wire compressing surface 1b abuts against the installed electric wire 2 in a compressive manner, the covering fastener 1 is firmly attached to the installed electric wire 2, and in this state the fastening surface 1e abuts against the covering from the side of the intended cutting point C, so that the fastening surface 1e receives the force acting on the covering 22 in the direction approaching the intended cutting point C, thereby restricting movement of the covering 22. Therefore, displacement of the covering 22 relative to the core wire 21 can be suppressed.

[0066] Moreover, since the wire compressing surface 1b has corners 17 at both ends in the width direction, the wire compressing surface 1b can easily bite into the coating 22. Therefore, the coating fastener 1 can easily compress and crush the coating 22 of the installed electric wire 2.

[0067] Furthermore, since the length of the wire compressing surface 1b in the width direction is shorter than the length in the direction intersecting the width direction (longitudinal or depth direction), the wire compressing surface 1b can easily bite into the coating 22. Therefore, the coating fastener 1 can easily compress and crush the coating 22 of the installed electric wire 2.

[0068] Furthermore, since the connecting portions 13 extend linearly, the distance between the compressed end portions 14 can be secured, and the opening 1d can be widened. This makes it easier to insert the installed electric wire 2 into the electric wire receiving area 1c.

[0069] Furthermore, since the compressed end surface 14a is a surface without corners, it is possible to prevent the wire 2 from being damaged by the compressed end surface 14a when the wire 2 is inserted into the wire receiving area 1c through the opening 1d.

[0070] Furthermore, because the wire compression surface 1b is a smooth surface, when compressing the coating 22, the compression force is concentrated in one area, which can prevent damage to the core wire 21. Note that damage to the core wire 21 refers to damage to the extent that the damaged area cannot withstand the tension applied during installation. For example, scratches that do not affect the durability of the installed wire 2, or small scratches on the surface of the core wire 21, are acceptable.

[0071] Furthermore, according to the method for cutting the overhead electric wire 2 of this embodiment, the covering fastener 1 is attached near the intended cutting point C of the overhead electric wire 2 in the covering fastening process, so that the tension at a predetermined point of the overhead electric wire 2 is relaxed in the tension relaxation process, and the overhead electric wire 2 is cut in the cutting process, and the overhead electric wire 2 is divided into one side and the other at the cutting point, so that the covering 22 can move toward the cutting point, and even if a force is applied to the covering in this state to move it toward the cutting point, the covering fastener 1 restricts the covering 22 from moving in the direction approaching the cutting point, so that the covering 22 can be prevented from shifting relative to the core wire 21.

[0072] Furthermore, by compressing the covering fastener 1 to the extent that it crushes the covering 22, the covering fastener 1 is firmly attached to the overhead electric wire 2. Therefore, the covering 22 can be prevented from shifting.

[0073] Furthermore, the covering fastener 1 crushes the covering 22 and compresses it to the extent that the inner surface of the covering fastener 1 comes into direct contact with the core wire 21, so that the covering fastener 1 comes into direct contact with the core wire 21, thereby preventing the covering fastener 1 from shifting relative to the core wire 21. Therefore, the covering 22 can be reliably fastened.

[0074] Furthermore, the covering fastener 1 compresses the installed electric wire 2 so that part of the inner surface of the covering fastener 1 comes into direct contact with the core wire 21 and the other part leaves the covering between the covering fastener 1 and the core wire 21, thereby preventing the core wire 21 from being damaged in the part where the covering fastener 1 does not come into contact with the core wire 21.

[0075] Furthermore, with respect to the installed electric wire 2 cut in the cutting step, it is possible to suppress displacement of the coating 22 with respect to the core wire 21 on both one side and the other side of the cut portion.

[0076] Furthermore, since the position where the covering fastener 1 is to be attached is determined using the guide member 5, it is easy to determine the position where the covering fastener 1 is to be attached to the overhead electric wire 2.

[0077] Furthermore, since the insulating cover 8 is the guide member 5, the insulating cover 8 can be used as both a cover and a guide, thereby improving the arrangements for cutting the installed electric wire 2.

[0078] Furthermore, since the sheath fastener 1 is positioned between the pair of wire grippers 41, even if the sheath 22 is pulled toward the intended cutting location C by the pulling tool, the sheath 22 can be reliably prevented from shifting.

[0079] Furthermore, since the portion compressed by the covering fastener 1 is covered with the insulating cover 8, it is possible to prevent current leakage from the portion where the covering fastener 1 is attached.

[0080] Furthermore, in the capping step, the cut portion 2B and the covering fastener 1 are covered with the cap 6, so that leakage of electricity from the cut portion 2B or the portion where the covering fastener 1 is attached can be suppressed.

[0081] Next, a method for cutting an installed electric wire 2 according to a second embodiment of the present invention will be described with reference to Fig. 13 to Fig. 15. The configuration of the sheath fastener 1 in the second embodiment is the same as that in the first embodiment.

[0082] The method for cutting an overhead electric wire 2 according to the second embodiment includes (1) a bypass line forming step, (2) a temporary attachment step of a pulling tool, (3) a sheath fastening step, (4) a final attachment step of a pulling tool, (5) a tension relief step, (6) a cutting step, (7) a cap attachment step, (8) a main installation step, (10) a re-conduction step, (11) an insulating cover attachment step, and (12) a pulling tool removal step. The sheath fastening step includes (3-1) a middle portion stripping step and (3-2) a sheath fastener attachment step. The method for cutting an overhead electric wire 2 according to the second embodiment differs from the first embodiment in (3) the sheath fastening step and (6) the cutting step. The method for cutting an overhead electric wire 2 according to the second embodiment also differs from the first embodiment in that it does not include (9) a cutting portion stripping step. In the following description, steps different from the first embodiment will be described, and descriptions of the same steps will be omitted.

[0083] (3-1) Middle part peeling process As shown in FIG. 13 , the (3-1) middle section stripping step is a step of stripping the coating 22 from the planned cutting point C and its vicinity to expose the core wire 21. In the middle section stripping step, the planned cutting point C is located approximately in the center of the exposed portion 2C, and the coating 22 is stripped from the planned cutting point C and its vicinity so that the length of the exposed portion 2C is sufficient to crimp the connector 7 and the core wire 21 in the re-conduction step. Specifically, in the middle section stripping step, a connector 7 is placed as a stripping guide member at the planned cutting point C, and the coating 22 is stripped off to a length that is the length of the connector 7 plus the width of three coating fasteners 1. Note that an insulating cover 8 can also be used as a stripping guide member, and the coating 22 can be stripped using the distance of a guide display portion 51 provided on the insulating cover 8 as a guide.

[0084] (3-2) Covering fastener installation process (3-2) The covering fastener attaching process is a process of attaching the covering fastener 1 to the exposed portion 2C of the core wire 21. In the covering fastener attaching process, the covering fastener 1 is attached to positions on one side and the other side of the planned cutting point C in the exposed portion 2C. In addition, in the covering fastener attaching process, the covering fastener 1 is also attached to the planned cutting point C. Specifically, in the covering fastener attaching process, the covering fastener 1 is attached to one end and the other end of the exposed portion 2C and to the planned cutting point C, which is a midpoint of the exposed portion 2C.

[0085] In the covering fastener attaching step, the covering fastener 1 is attached to the exposed core wire 21. Specifically, the covering fastener 1 is compressed relative to the core wire 21 to an extent that the covering fastener 1 does not shift relative to the core wire 21 in the extending direction of the installed electric wire 2. In other words, the covering fastener 1 is attached to the installed electric wire 2 so as to compress the core wire 21 from the radially outer side to the radially inner side, and the wire compressing surface 1b presses the outer surface of the core wire 21 radially inward, thereby firmly attaching the covering fastener 1 to the installed electric wire 2.

[0086] When the covering fastener 1 is attached to the overhead electric wire 2, the fastening surface 1e of the covering fastener 1 and the adjacent portion 2A adjacent to the fastening surface 1e of the covering 22 face each other in the extension direction of the overhead electric wire 2. Specifically, the thick portion 221 of the covering 22 in the adjacent portion 2A faces the fastening surface 1e in the extension direction of the overhead electric wire 2, and the thick portion 221 of the adjacent portion 2A can abut against the fastening surface 1e (see FIG. 15).

[0087] Furthermore, the covering fastener 1 attached to the intended cutting location C bundles together the plurality of wires 211 that make up the core wire 21. Therefore, when the core wire 21 is cut in the cutting step described below, the wires 211 can be prevented from coming apart.

[0088] (6) Cutting process As shown in Fig. 14, the (6) cutting step is a step of cutting the installed electric wire 2 at the planned cutting point C, and in this embodiment, the core wire 21 is cut. Specifically, in the cutting step, the core wire 21 is cut at one end and the other end of the covering fastener 1 attached to the planned cutting point C, and the installed electric wire 2 is divided into one side and the other side at the planned cutting point C. Note that this is not the only case, and for example, it is also possible to cut both the core wire 21 and the covering fastener 1 at a midpoint in the width direction of the covering fastener 1 attached to the planned cutting point C.

[0089] Even after the cutting is complete, the installed electric wire 2 is still pulled by the hauling tool 4, so the portion of the installed electric wire 2 gripped by the wire gripper 41 is pulled toward the cutting location. Therefore, a force is applied to the covering 22 along the outer surface of the core wire 21 in a direction that moves the covering 22 toward the cutting location. However, as shown in FIG. 15 , since the covering fastener 1 is attached between the wire gripper 41 and the cutting location, when the covering 22 tries to move toward the cutting location, the adjacent portion 2A abuts against the fastening surface 1e, and movement of the covering 22 relative to the core wire 21 is restricted. Therefore, displacement of the covering 22 relative to the core wire 21 can be suppressed.

[0090] According to the covering fastener 1 as described above, the covering fastener 1 is attached to the exposed portion 2C of the core wire 21 so as to compress the core wire 21 from the radially outward direction, so that the covering fastener 1 can be reliably fixed to the core wire 21 and can restrict movement of the covering 22 by contacting the covering 22 from the intended cutting portion C side as the covering 22 approaches the intended cutting portion C. Therefore, displacement of the covering 22 relative to the core wire 21 can be suppressed.

[0091] Furthermore, according to the method for cutting the installed electric wire 2 of this embodiment, the coating fastener 1 is attached to the exposed portion 2C from which the coating 22 has been stripped in the middle portion stripping process in the coating fastening process, so that the coating 22 can be prevented from shifting relative to the core wire 21.

[0092] Furthermore, since the covering fasteners 1 are attached to both one end and the other end of the exposed portion 2C, it is possible to suppress displacement of the covering 22 relative to the core wire 21 on both one and the other sides of the cut portion.

[0093] Although the embodiments of the present invention have been described above using examples, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist of the present invention.

[0094] For example, the covering fastener 1 has been described as being attached to one side and the other side of the intended cutting point C, but this is not limited to this case, and it can also be configured to be attached to only one side or the other side of the intended cutting point C.

[0095] The order of the steps can be changed as needed. For example, the sheath fastener 1 can be attached first, and then the pulling tool 4 can be temporarily attached to the installed electric wire 2, or the tension on the electric wire can be relieved before the sheath fastener 1 is attached.

[0096] Furthermore, the configuration of the pulling tool 4 is not limited to the configuration shown as an example, and various configurations that can relieve the tension on the electric wires can be adopted.

[0097] Furthermore, the configuration of the covered fastener 1 is not limited to the configuration described above. For example, as shown in Figures 16 to 19, the covered fastener 1 may be configured to include a fall-off prevention means 18 for preventing the covered fastener 1 from falling off from the compression tool 9. The fall-off prevention means 18 engages with the compression tool 9 to prevent the covered fastener 1 from falling off from the compression tool 9.

[0098] 16, the coated fastener 1 can be configured to include an elastic body 181 as the falling-off prevention means 18. The elastic body 181 is provided on the tool contact surface 1a and configured to be compressed between the jaws (e.g., upper jaw portion 9U) of the compression tool 9 and the tool contact surface 1a. With this configuration, the restoring force of the elastic body 181 presses the coated fastener 1 against the jaws (e.g., lower jaw portion 9D) of the compression tool 9, so that the coated fastener 1 can be prevented from falling off from the compression tool 9.

[0099] 17, the covering fastener 1 may also be configured to include, as the falling-off prevention means 18, a strip-shaped tape 182 configured so that one surface can be adhered to another member. The tape 182 is provided, for example, on the fastening surface 1e, and configured so that one end of the strip in the longitudinal direction adheres to the fastening surface 1e and the other end adheres to a part of the compression tool 9. With this configuration, the covering fastener 1 and the compression tool 9 are connected by the tape 182, thereby preventing the covering fastener 1 from falling off from the compression tool 9. The tape 182 may also be configured as a double-sided tape, with one surface adhered to the tool contact surface 1a and the other surface adhered to the jaw of the compression tool 9. With this configuration, the covering fastener 1 and the compression tool 9 are connected by the tape 182, thereby preventing the covering fastener 1 from falling off from the compression tool 9.

[0100] 18, the covering fastener 1 can also be configured to include locking portions 183 as the falling-off prevention means 18. The locking portions 183 are plate-like bodies arranged at one end and the other end of the covering fastener 1 in the width direction, and are configured to restrict movement of the covering fastener 1 in the width direction relative to the compression tool 9 by being positioned on one side and the other side of the compression tool 9 in the width direction. The locking portions 183 are also configured to be rotatable in a direction toward and away from the compression tool 9. With this configuration, the locking portions 183 can restrict movement of the covering fastener 1 in the width direction relative to the compression tool 9, thereby preventing the covering fastener 1 from falling off from the compression tool 9.

[0101] 19, the sheathing fastener 1 may also be configured to include a binding 184 as the falling-off prevention means 18. The binding 184 is a long, cord-like piece and is provided at one end and the other end of the first compression section 11 in the width direction. Each binding 184 is configured so that one end in the longitudinal direction is fixed to the first compression section 11 and the other ends of both bindings 184 can be connected to each other. The binding 184 is, for example, a metal wire. With this configuration, the sheathing fastener 1 can be connected to the compression tool 9 by the binding 184, thereby preventing the sheathing fastener 1 from falling off from the compression tool 9. Note that the binding 184 is not limited to being fixed to the first compression section 11, but may also be fixed to the second compression section 12, the connecting section 13, or the like. Note that the binding 184 is not limited to being linear, but may be configured, for example, as a strip, with both ends in the longitudinal direction connectable by connecting means such as hook-and-loop fasteners.

[0102] Furthermore, although the sheath fastener 1 has been described as having a vertically symmetrical shape, the present invention is not limited to such a configuration and may have a vertically asymmetrical configuration. For example, as shown in Fig. 20, the second compression portion 12 may have a shorter vertical length than the first compression portion 11. Even with such a configuration, the entire sheath fastener 1 is deformed by compression, and the entire installed electric wire 2 can be compressed, thereby fastening the sheath 22.

[0103] 21 and 22, the covering fastener 1 can be configured to crush the covering 22 but not the core wire 21. In such a case, the covering fastener 1 does not come into contact with the core wire 21, thereby preventing the core wire 21 from being damaged. Even with this configuration, the covering 22 is pressed against the core wire 21 by the covering fastener 1, preventing the covering 22 from shifting relative to the core wire 21.

[0104] Next, a description will be given of a method for attaching and detaching the electric wire 20 using the covering fastener 1. The configuration of the covering fastener 1 is the same as that of the above-described embodiment.

[0105] In the method for attaching and detaching the electric wire 20, the electric wire 20 is attached to or detached from a utility pole P serving as a support. The electric wire 20 is attached to, for example, an insulator (not shown) provided on the utility pole P, and detached from the insulator. The configuration of the electric wire 20 is the same as that of the above-mentioned erected electric wire 2. That is, the electric wire 20 includes a core wire 21 made of a conductor and a covering 22 made of a non-conductor that covers the core wire. Such an electric wire 20 is erected between a pair of supports (electric poles P) that are arranged at a distance from each other.

[0106] First, a wire installation method for installing the wire 20 on the utility pole P will be described with reference to Fig. 23. The wire installation method includes (1) a lifting step, (2) a tension adjuster attachment step, (3) a sheath fastening step, (4) a drawing step, (5) a wire installation step, (6) a tension adjuster removal step, and (7) an insulation step.

[0107] (1) Lifting process (1) The lifting process is a process of lifting the electric wire 20 to bring the end 20D in the extension direction of the electric wire 20 closer to the attachment position of the electric wire 20 on the utility pole P. The attachment position of the electric wire 20 on the utility pole P is the upper end portion of the utility pole P, and in the lifting process, the electric wire 20 is lifted up to the upper end portion of the utility pole P. In the lifting process, for example, the electric wire 20 is lifted using a rope to bring the end 20D of the electric wire 20 closer to the utility pole P. Note that this configuration is not limited to this, and for example, the electric wire 20 can be moved from one utility pole to the other utility pole P (the utility pole P to which the electric wire 20 is attached) by running the electric wire 20 along a rope that is stretched in advance between a pair of utility poles on which the electric wire 20 is to be installed. In either case, the end 20D of the electric wire 20 comes closer to the utility pole P.

[0108] (2) Tension adjustment device installation process (2) The tension adjusting device mounting step is a step of mounting the tension adjusting device 40 to the end 20D of the electric wire 20 and the utility pole P. The tension adjusting device 40 includes a wire gripping device 41 that grips the electric wire 20, a support body mounting part 405 that is mounted on the electric pole P, and the tension adjusting part 401, one end of which is connected to the wire gripping device 41 and the other end of which is connected to the support body mounting part 405. The configuration of the wire gripping device 41 is the same as that of the wire gripping device 4 of the pulling tool 4 in the above-described embodiment. That is, the wire gripping device 41 grips the installed electric wire 2 from outside the sheath 22 and restricts the installed electric wire 2 from moving relative to the wire gripping device 41 in the direction opposite to the pulling direction. The support body mounting part 405 is an annular member that can be hung on the electric pole P. Specifically, the support body mounting part 405 is an annular rope that can be hung on the electric pole P, and is engaged with, for example, an arm or a scaffolding bolt (not shown) of the electric pole P. The tension adjusting unit 401 is a wire tensioner. The tension adjusting unit 401 is configured to connect the wire gripper 41 and the support mounting unit 405 and to draw the wire gripper 41 to the support mounting unit 405. Specifically, the tension adjusting unit 401 includes a pulling main body 402 that pulls the wire gripper 41 toward the support mounting unit 405 and a wire portion 403 that extends from the pulling main body 402 toward the wire gripper 41. The pulling main body 402 is configured to pull the wire gripper 41 toward the support mounting unit 405 by winding up the wire portion 403. The pulling main body 402 includes a winding operation unit 404 that is operated to wind up the wire portion 403. The pulling main body 402 is also configured to restrict the wound wire portion 403 from being unwound, and specifically, is a winder having a ratchet gear.

[0109] In the tension adjusting device installation process, the wire gripping device 41 is installed on the electric wire 20, and the support body installation part 405 is installed on the utility pole P. At this time, the wire part 403 is pulled out to a length sufficient for installing the wire gripping device 41 and the support body installation part 405. The wire gripping device 41 is installed on the end part 20D of the electric wire 20, from above the coating 22 of the electric wire 20, at a position away from the end part 20E of the electric wire 20 on the opposite side.

[0110] (3) Covering process (3) The sheath fastening step is a step of attaching the sheath fastener 1 to the end 20D of the electric wire 20. The method of attaching the sheath fastener 1 to the electric wire 20 is the same as in the above-described embodiment. That is, the sheath fastener 1 is attached by compressing the electric wire 20 with a compression tool 9. In this embodiment, the sheath fastener 1 is attached to a position between the position where the wire gripper 41 is attached to the electric wire 20 and the end 20E of the electric wire 20. Furthermore, if there is a portion where the sheath 22 has been stripped off, for example, for electrical connection with another installed electric wire 2, at a position on the opposite side of the end 20E of the electric wire from the position where the sheath fastener 1 is attached to the electric wire 20, the distance from the stripped portion to the sheath fastener 1 is preferably 1000 mm or more, and more preferably 1200 mm or more. With this configuration, when the sheath 22 tries to shift, it is more likely to receive resistance from the core wire 21. Therefore, combined with the effect of the sheath fastener 1, this can suppress shifting of the sheath 22 relative to the core wire 21.

[0111] (4) Pulling process (4) The pulling-in process is a process of pulling the end 20D of the electric wire 20 toward the utility pole P. Specifically, in the pulling-in process, the wire portion 403 is wound up, the distance between the wire gripper 41 and the support body mounting portion 405 is shortened, and the wire gripper 41 is pulled toward the utility pole P, thereby bringing the end 20D of the electric wire 20 closer to the utility pole P. In the pulling-in process, the end 20D of the electric wire 20 is pulled toward the utility pole P to an extent that the end 20D of the electric wire 20 can be attached to the utility pole P. Here, the portion of the electric wire 20 gripped by the wire gripper 41 is pulled toward the end 20E. Therefore, a force is applied to the coating 22 in a direction that moves the coating 22 toward the end 20E along the outer surface of the core wire 21. However, since the sheath fastener 1 is attached between the wire gripper 41 and the end 20E, when the sheath 22 attempts to move toward the end 20E, the adjacent portion 2A abuts against the fastening surface 1e, restricting the movement of the sheath 22 relative to the core wire 21. Therefore, the sheath 22 can be prevented from shifting relative to the core wire 21.

[0112] (5) Wire installation process (5) The electric wire attaching process is a process of attaching the end 20D of the electric wire 20 to the utility pole P. Specifically, in the electric wire attaching process, the end 20D of the electric wire 20 pulled toward the utility pole P is attached to a retaining clamp provided on an insulator of the utility pole P. In this process, the electric wire 20 is supported by the utility pole P.

[0113] (6) Tension adjustment device removal process (6) The tension adjusting device removal process is a process of removing the tension adjusting device 40 from the electric wire 20 and the utility pole P. Specifically, the support body mounting part 405 is removed from the utility pole P, and the wire gripping tool 41 is removed from the electric wire 20. Note that the covering fastener 1 remains attached to the electric wire 20.

[0114] (7) Insulation process (7) The insulating process is a process of insulating the portion of the electric wire 20 where the covering fastener 1 is attached. Specifically, in the insulating process, the covering fastener 1 is insulated by wrapping a tape made of an insulating material around the outer periphery of the covering fastener 1. Also, in the insulating process, a clamp cover made of an insulating material is attached to the above-mentioned retaining clamp, thereby insulating the electric wire 20 and the retaining clamp. Note that this configuration is not limited to this, and for example, the covering fastener 1 can be insulated by attaching an insulating cover 8 to the portion where the covering fastener 1 is attached, or the covering fastener 1 can be insulated by covering the portion where the covering fastener 1 is attached with a clamp cover together with the retaining clamp.

[0115] Through the above steps, the attachment of the electric wire 20 to the support (electric pole P) is completed.

[0116] Next, a method for removing the electric wire 20 from the support body will be described. The electric wire removal method includes (1) a tension adjuster attachment step, (2) a covering fastening step, (3) a drawing step, (4) an electric wire removal step, (5) a tension adjuster removal step, and (6) a hanging step. The (1) tension adjuster attachment step, (2) covering fastening step, and (3) drawing step are the same as the steps in the above-described attachment method, except that they are performed in a state where the electric wire 20 is attached to the electric pole P. Furthermore, the (5) tension adjuster removal step is the same as the above-described tension adjuster removal step, except that it is performed in a state where the electric wire 20 has been removed from the electric pole P.

[0117] (3) By the pulling-in process, the wire gripping device 41 is pulled toward the utility pole P, thereby reducing the tension applied to the portion of the utility pole P where the electric wire 20 is attached (the retention clamp). Here, the portion of the electric wire 20 gripped by the wire gripping device 41 is pulled toward the end 20E. As a result, a force is applied to the covering 22 along the outer surface of the core wire 21 in a direction that moves the covering 22 toward the end 20E. However, because the covering fastener 1 is attached between the wire gripping device 41 and the end 20E, when the covering 22 attempts to move toward the end 20E, the adjacent portion 2A abuts against the fastening surface 1e, restricting movement of the covering 22 relative to the core wire 21. As a result, it is possible to prevent the covering 22 from shifting relative to the core wire 21.

[0118] (4) The electric wire detaching step is a step of detaching the electric wire 20 from the utility pole P. Specifically, the electric wire 20 is detached from the retention clamp of the utility pole P, and the electric wire 20 is brought into a detached state from the utility pole P.

[0119] (6) The hanging process is a process of hanging the electric wire 20 and lowering it to the ground where the utility pole P is installed. Specifically, in the hanging process, for example, the electric wire 20 is hung using a rope and the electric wire 20 is lowered.

[0120] Through the above steps, the removal of the electric wire 20 from the support (electric pole P) is completed.

[0121] According to the above-described method for attaching and detaching an electric wire, the covering fastener 1 is attached to the electric wire 20 in the covering fastening step, and then the electric wire 20 is pulled toward the support body by the tension adjusting device 40. Therefore, even if a force is applied to the covering 22 to move toward the end 20D of the electric wire 20 in the extension direction of the electric wire 20, the covering fastener 1 prevents the covering 22 from moving toward the end 20D of the electric wire 20. Therefore, it is possible to prevent the covering 22 from shifting relative to the core wire 21.

[0122] Furthermore, with the covering fastener 1 as described above, even if a force is applied to the covering 22 to move it toward the end 20D of the electric wire 20 by pulling the electric wire 20, the covering fastener 1 attached to the end 20D of the electric wire 20 prevents the covering 22 from moving toward the end 20D in the extension direction of the electric wire 20, thereby preventing the covering 22 from shifting relative to the core wire 21.

[0123] In the above-described method for attaching and detaching an electric wire, the case where the tension adjuster 40 is attached to the electric wire 20 and the support body and then the covering fastener 1 is attached to the electric wire 20 has been described as an example, but the present invention is not limited to this configuration, and the covering fastener 1 may be attached to the electric wire 20 and then the tension adjuster 40 may be attached to the electric wire 20. In any case, it is sufficient that the covering fastener 1 is attached before the drawing-in step. [Explanation of symbols]

[0124] 1...coating fastener, 1a...tool contact surface, 1b...wire compression surface, 1c...wire accommodating area, 1d...opening, 1e...fastening surface, 11...first compression portion, 12...second compression portion, 13...connecting portion, 14...compression end portion, 14a...compression end surface, 15...compression main body portion, 16...compression connecting portion, 17...corner portion, 18...fall-off prevention means, 181...elastic body, 182...tape, 183...locking portion, 184...bind, 2...overhead electric wire, 2A...adjacent portion, 2B...cut portion, 2C...exposed portion, 21...core wire, 211...element wire, 22...coating, 221...thick portion, 3...bypass line, 31...bypass line, 32... Construction switchgear, 33...bypass mounting portion, 4...pulling tool, 41...wire gripper, 42...pulling portion, 43...receiving portion, 44...wire gripping connection portion, 45...cam portion, 46...insulating rod portion, 47...extension portion, 471...extension main body portion, 472...extension operation portion, 48...mounting auxiliary portion, 5...guide member, 51...guide display portion, 6...cap, 7...connector, 8...insulating cover, 9...compression tool, 9D...lower jaw portion, 9U...upper jaw portion, C...planned cutting location, 40...tension adjustment device, 401...tension adjustment portion, 402...pulling main body portion, 403...wire portion, 404...winding operation portion, 405...support mounting portion, P...utility pole

Claims

1. A covering fastener used in a method for cutting an overhead electric wire, the method including: a tension relief step of grabbing one side and the other side of a predetermined region including a planned cutting point where an overhead electric wire having a core wire made of a conductor and a covering made of a non-conductor and covering the core wire is to be cut at a predetermined position in the extension direction, together with the covering, and relatively pulling the predetermined region toward the planned cutting point, thereby releasing the tension acting on the predetermined region; and a cutting step of cutting the overhead electric wire at the planned cutting point in the predetermined region where the tension has been released in the tension relief step, A sheathing fastener that is attached to the installed electric wire at a position near the intended cutting point in the specified region by compressing the installed electric wire from the outside to the inside of the diameter, and is configured to restrict the sheathing from moving in a direction approaching the intended cutting point relative to the core wire.

2. 2. The covering fastener according to claim 1, comprising: a wire compression surface that contacts the overhead electric wire from the outside of the diameter and compresses the overhead electric wire inward of the diameter; and a fastening surface that abuts against the covering that is moving to the intended cutting location from the side of the intended cutting location.

3. The sheath fastener according to claim 1 or 2, configured to be attachable to the overhead electric wire by compressing the sheath so as to crush the sheath from the outer diameter to the inner diameter.

4. The method for cutting the installed electric wire includes a step of stripping off the covering of at least a part of a region including the intended cutting location to form an exposed portion in which the core wire is exposed, The covering fastener according to claim 1 or 2, wherein the covering fastener is attached to the exposed portion of the core wire so as to compress the core wire from a radially outward direction.

5. A covering fastener used in a method for attaching and detaching an electric wire, the method including: a drawing step of grasping an end of an electric wire in an extension direction, including a core wire made of a conductor and a covering made of a non-conductor and covering the core wire, together with the covering, and drawing the end of the electric wire toward the end in the extension direction; and a step of attaching or detaching the end of the electric wire drawn in the drawing step to or from a support that supports the electric wire, A covering fastener is attached to the end of the electric wire by compressing the electric wire from the outside to the inside of the diameter, and is configured to restrict the covering from moving in a direction approaching the end side relative to the core wire in the extension direction of the electric wire.

6. The covering fastener according to claim 5 , configured to be attachable to the electric wire by compressing the covering so as to crush the covering from the outer diameter to the inner diameter.

Images