Come-along for retaining overhead wires and temporary support method for overhead wire tension using it

Abstract

To provide a strong come-along for drawing an overhead line capable of temporarily gripping the overhead line by setting the overhead line on the overhead line by a remote operation from an iron tower without using a midair stunt machine and a self-propelled machine.SOLUTION: A come-along 1 has a gripping device 2 and an operation bar 3. The gripping device 2 grips an overhead line G between upper and lower clamps 5 and 6 at a position apart from an iron tower T on the overhead line G, and draws the overhead line to the iron tower T by towing means. The operation bar 3 slips the gripping device 2 to a setting position on the overhead line G to be sent by a remote operation from the iron tower T, and makes the upper and the lower clamps 5 and 6 temporarily grip the overhead line G. The upper clamp 5 falls in conjunction with rotations around an axis of the operation bar 3, and temporarily grips the overhead line G by an initial gripping force with respect to the lower clamp 6. A link mechanism 7 is connected to the lower clamp 6 so as to raise the lower clamp 6 in accompany with towing of the towing means, and thereby is provided so that the overhead line G may be gripped by gripping force added to the initial gripping force with respect to the upper clamp 5.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] In construction work such as replacing an overhead line such as an existing overhead ground wire or replacing ancillary equipment around the overhead line, the overhead line is pulled to the tower and temporarily fastened while the work of disconnecting or connecting the overhead line from the tower is being carried out, and the tension is temporarily transferred to the tower to remove tension from the work area. The present invention relates to a come-along used in such construction work to pull the overhead line to the tower side and temporarily support it. [Background technology]

[0002] For example, when disconnecting an existing overhead line from its connection to a tower, the overhead line is separately tensioned with a come-along and temporarily fastened to the tower, and the tension at the connection is temporarily applied to the tower before work can begin. In this case, the come-along must be attached to the overhead line at a position farther away from the tower than the connection. The come-along described in Patent Document 1 includes a two-part wedge member that grips an electric wire, a cylindrical come-along body into which the wedge member is inserted, and an arm that connects to the come-along body. The outer peripheral surface of the wedge member and the inner peripheral surface of the come-along body are tapered toward the insertion side. After the wedge member with the electric wire inserted is attached to the come-along body and connected to a steel tower, the arm is pulled in with a chain block or the like, causing the wedge member and the come-along body to grip the electric wire and tighten the wire. The come-along described in Patent Document 2 has an arm connected to the wire of a chain block coupled to a steel tower, and a clamp equipped with a pair of opposing clamping pieces that receive and grip the electric wire inside, connected by a link. The pair of clamping pieces grip the electric wire and can tension it by the relative movement between the arm and the clamp in the wire extension direction as the arm is pulled in by the chain block. The self-propelled come-along described in Patent Document 3 comprises a main body that can move by passing the overhead electric wire between it and a wedge, and a self-propelled vehicle positioned behind the main body in the direction of travel. The self-propelled vehicle uses a push rod to push the main body along the overhead electric wire, transporting it to a predetermined gripping position. After the self-propelled vehicle is driven in reverse to retrieve the wire, the wire connected to the handle of the main body is pulled by a winch or the like, and the wedge is pushed into the main body via a cam mechanism, thereby gripping and pulling the electric wire. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 58-193807 [Patent Document 2] Patent No. 4121081 [Patent Document 3] Publication number 3-006100 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0004] In both the come-alongs described in Patent Documents 1 and 2, installation and removal work requires a worker to ride on a flying machine suspended from the overhead wire and move to a position beyond the connection point (for example, the tip of the insulator).The use of a flying machine itself is prohibited for small-diameter overhead wires, so there is a problem in that this cannot be applied. The self-propelled come-along described in Patent Document 3 cannot be used if there are obstacles such as dampers on the electric wires, and because it requires a driving source such as a power source, it is heavy and overall workability is reduced.In addition, there are problems such as the electrical equipment deteriorating quickly over time and the difficulty of recovering equipment due to breakdowns, which are prone to problems due to the vulnerability of the electrical equipment. Therefore, the present invention aims to provide a robust come-along for pulling in overhead wires that can be attached to and detached from overhead wires by a worker on a steel tower by remote control without using a flying machine or an electrically powered self-propelled machine, and also to provide a construction method using the same for temporarily supporting the tension of the overhead wire on the steel tower during construction. [Means for solving the problem]

[0005] In the following description, reference will be made to the reference numerals in the accompanying drawings, but the present invention is not limited thereto. To solve the above problems, the come-along 1 of the present invention comprises a gripping device 2 and an operating rod 3 connected thereto. The gripping device 2 grips the overhead wire G between upper and lower clamps 5, 6 at a position away from the tower T on the overhead wire G that is fastened to the tower T, and is pulled to the tower T by a towing means such as a chain block C. The operating rod 3 is connected to the gripping device 2 and is provided so that the gripping device 2 can be remotely operated from above the tower so that the gripping device 2, which has received the overhead wire G between the open upper and lower clamps 5, 6, slides over the overhead wire G to an installation position, pulls it back, and brings the upper and lower clamps 5, 6 closer to each other to temporarily grip the overhead wire G with an initial gripping force, and then separates them to release the grip. The gripping device 2 comprises an upper clamp 5 supported on the main body 4 so as to be movable up and down relative to the overhead wire G, a lower clamp 6 supported on the main body 4 opposite the upper clamp 5 so as to be movable up and down relative to the overhead wire G, and a link mechanism 7 supported on the main body 4, connected at one end to a traction means, and connected at the other end to the lower clamp 6. The upper clamp 5 is arranged to descend relative to the main body 4 in conjunction with the rotation of the operating rod 3 about its axis, thereby temporarily gripping the overhead wire G between itself and the lower clamp 6, and then to rise to release the grip. The link mechanism 7 is arranged to push up the lower clamp 6 as the traction means pulls, thereby gripping the overhead wire G between itself and the upper clamp 5 with a gripping force that is additional to the initial gripping force. Furthermore, the method for temporarily supporting an overhead wire G using the come-along 1 of the present invention includes a first step of taking the overhead wire G between the upper and lower clamps 5, 6 of the gripping device 2 with the upper and lower clamps 5, 6 open, and supporting the gripping device 2 on the overhead wire G; a second step of sliding the gripping device 2 on the overhead wire G using the operating rod 3 connected to the gripping device 2 to move it to a predetermined installation position; a third step of rotating the operating rod 3 in one direction around its axis to lower the upper clamp 5 relative to the main body 4, thereby temporarily gripping the overhead wire G between the upper and lower clamps 5, 6 with an initial gripping force; and a third step of pulling one end of the link mechanism 7 with a pulling means to push up the lower clamp 6 and hold the upper clamp 5. The method includes a fourth step of temporarily supporting the overhead wire G by holding the overhead wire G between the upper and lower clamps 5 and 6 with a holding force added to the initial holding force, thereby removing the tension on the overhead wire G at the specified construction location; a fifth step of reducing the holding force between the upper and lower clamps 5 and 6 by releasing the traction by the traction means; a sixth step of rotating the operating rod 3 connected to the holding device 2 in the opposite direction around its axis to raise the upper clamp 5 relative to the main body 4, opening the gap between the upper clamp 5 and the lower clamp 6, thereby releasing the grip on the overhead wire G and releasing the tension; and a seventh step of pulling the operating rod 3 connected to the holding device 2 to pull the holding device 2 along the overhead wire G to the hand and removing it from the overhead wire G. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a robust overhead line pulling come-along that can be easily attached to and detached from an overhead line by a worker on a steel tower via remote control without using a flying machine or an electrically powered self-propelled machine, and a temporary overhead line support construction method that uses this to perform work safely and quickly. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a perspective view of a come-along for holding an overhead wire according to the present invention; FIG. [Figure 2] FIG. 2 is an explanatory diagram of the come-along of FIG. 1 in use. [Figure 3]FIG. 1 is a front view of a come-along for fastening an overhead wire according to the present invention. [Figure 4] FIG. 2 is a front view of a gripping device in the come-along of FIG. 1. [Figure 5] FIG. 2 is a right side view of the gripping device in the come-along of FIG. 1. [Figure 6] FIG. 2 is a left side view of the gripping device in the come-along of FIG. 1. [Figure 7] FIG. 2 is a rear view of the gripping device in the come-along of FIG. [Figure 8] 8 is a cross-sectional view taken along the line VIII-VIII in FIG. 4. [Figure 9] 9 is a cross-sectional view taken along line IX-IX in FIG. 4. [Figure 10] 2A and 2B show the operating rod of the come-along of FIG. 1, in which FIG. 2A is a front view and FIG. 2B is a plan view. [Figure 11] 2A and 2B show the operation process (open position) of the come-along of FIG. 1, in which FIG. 2A is a front view and FIG. 2B is a side view. [Figure 12] 2A and 2B show the operation process (closed position) of the come-along of FIG. 1, in which (A) is a front view and (B) is a side view. [Figure 13] 2A and 2B show the operation process (temporary grip position) of the come-along of FIG. 1, in which (A) is a front view and (B) is a side view. BEST MODE FOR CARRYING OUT THE INVENTION

[0008] An embodiment of a come-along for holding an overhead wire according to the present invention will be described with reference to the drawings.

[0009] For example, as shown in Figure 2, in construction work such as replacing an existing overhead line G that is attached to a steel tower T, the overhead line G is temporarily secured to the steel tower T and tensioned while the overhead line G is being removed from the insulator string I. The Come Along 1 is used to grasp the overhead line G in front of the removal point with the gripping device 2, and pull the overhead line G to the steel tower T via a towing wire W, chain block C, etc. to temporarily support it, and after the construction work is completed, it is removed from the overhead line G and recovered.

[0010] As shown in Figures 1 and 3, the come-along 1 comprises a gripping device 2 and an operating rod 3. The gripping device 2 is placed on an overhead wire G, such as an existing overhead ground wire, that is fastened to a steel tower T, and grips the overhead wire G, allowing it to be pulled by a chain block C or the like on the steel tower T via a towing wire W.

[0011] The operating rod 3 can be connected and disconnected to the gripping device 2, and by operating it from the tower T, the gripping device 2 is sent out to a predetermined installation position on the overhead wire G, and after an initial gripping force is applied to the gripping device 2 against the overhead wire G by remote control, it is disconnected from the gripping device 2.

[0012] 4 to 9, the gripping device 2 comprises a main body 4, an upper clamp 5 supported on the main body 4 so as to be movable up and down relative to the main body 4 and placed on the overhead wire G, and a lower clamp 6 opposed to and below the upper clamp 5 and supported on the main body 4 via a link mechanism 7 so as to be movable up and down relative to the main body 4. The link mechanism 7 is supported on the main body 4, connected to the pulling wire W at one end, and connected to the lower clamp 6 at the other end.

[0013] The upper clamp 5 is configured to descend relative to the main body 4 in conjunction with the rotation of the operating rod 3 in one direction around its axis, thereby temporarily gripping the overhead wire G with an initial gripping force between it and the lower clamp 6, and to rise and release the grip by rotation in the other direction.

[0014] The link mechanism 7 is connected to the lower clamp 6 so as to push up the lower clamp 6 as the pulling wire W is pulled, thereby gripping the overhead wire G between the upper clamp 5 with a gripping force that is additional to the initial gripping force.

[0015] As shown in Figures 5 and 6, the main body 4 of the gripping device 2 comprises a flat support plate portion 41 arranged along the overhead wire G on one side (rear side) of the overhead wire G in the direction perpendicular to the wire extension, and a threaded cylindrical portion 42 provided to protrude from the upper part of the support plate portion 41 onto the front overhead wire G, as best shown in Figures 7, 8 and 9. A plurality of ribs 411 are formed on the rear side of the support plate portion 41.

[0016] As shown in Figures 5 and 6, the upper clamp 5 is provided on the front side of the support plate 41 and includes a clamp body 51 that is placed on the overhead wire G, and a threaded rod 52. As shown in Figures 7 and 8, the threaded rod 52 extends upward from the center of the clamp body 51 so as to be rotatable about its axis, is threadedly engaged with the threaded cylindrical portion 42, and can be connected and disconnected at its upper end to the tip of the operating rod 3 via the transmission mechanism 8. The threaded rod 52 rotates forward and backward when the operating rod 3, which is connected to the transmission mechanism 8, is rotated about its axis, and moves up and down along the threaded cylindrical portion 42 together with the clamp body 51 relative to the main body 4. When the clamp body 51 is placed on the overhead wire G and the clamp body 51 moves down relative to the main body 4, the main body 4 is pulled up together with the lower clamp 6 relative to the overhead wire G.

[0017] As clearly shown in Figure 4, guide members 53 are fixed to both the front and rear ends in the wire extension direction of the clamp body 51. As clearly shown in Figures 5 and 6, the guide members 53 extend forward from the clamp body 51 in the direction perpendicular to the wire extension so as to be hung on the overhead wire G, and have a roughly V-shaped notch that opens downward so as to slide the overhead wire G and guide it below the upper clamp 5 when the gripping device 2 is hung on the overhead wire G.

[0018] As clearly shown in Figures 4 and 8, the transmission mechanism 8 is provided in a gear case 81. The upper end of the threaded rod 52 and the inner end of a connecting shaft 82 that connects the operating rod 3 are received in the gear case 81 so as to be rotatable about their respective axes in directions perpendicular to each other. A connecting plate 85 is pivotally supported on the connecting shaft 82 by a pivot pin 82a. The connecting plate 85 is provided with a detachable rod 85a at its tip that protrudes in a direction perpendicular to the wire extension. Bevel gears 83 and 84 that are fixed to the upper end of the threaded rod 52 and the inner end of the connecting shaft 82, respectively, mesh within the gear case 81, and the rotation of the connecting shaft 82 is transmitted to the threaded rod 52.

[0019] 4 and 8, a flat pinion support plate 9 extending downward parallel to the support plate portion 41 is fixed to the front side surface of the gear case 81 with bolts 91. A pair of pinion gears 10, one at the front and one at the rear in the extension direction, are supported by shafts 101 on the rear side surface of the pinion support plate 9.

[0020] A shutter plate 11 is provided so as to overlap the pinion support plate 9 and be able to move up and down relative to it. The shutter plate 11 closes the front opening between the upper and lower clamps 5, 6 when the gripping device 2 is moved over the overhead wire G, thereby preventing the gripping device 2 from derailing from the overhead wire G. As shown in Figures 7, 8, and 9, a vertical rack 12 that meshes with the pinion gear 10 is attached to the front and rear vertical edges of the shutter plate 11 in the wire extension direction with bolts 121, 122. As shown in Figure 9, the mounting seat of the rack 12 is formed with a vertical guide groove 123 that slidably meshes with the vertical edge of the pinion support plate 9. The shutter plate 11 is guided by both edges of the pinion support plate 9 that fit into the guide grooves 123, and moves up and down relative to the pinion support plate 9. In the upper open position, it opens the side openings between the upper and lower clamps 5, 6 to allow the overhead wire G to be received between the upper and lower clamps 5, 6, and in the lower closed position, it closes the side openings to prevent the gripping device from derailing from the overhead wire G. A pair of vertical elongated holes 11a formed in the shutter plate 11 are elongated holes that allow the protruding portion of the shaft 101 of the pinion gear 10 to escape.

[0021] 9, another rack 13 that meshes with the pinion gear 10 is fixed to the threaded cylindrical portion 42. When the threaded rod 52 moves up and down together with the pinion support plate 9 relative to the threaded cylindrical portion 42, the pinion gear 10 that meshes with the rack 13 rotates, causing the shutter plate 11 to move up and down in the same direction. Therefore, when the threaded rod 52 rotates and moves down relative to the main body 4 together with the upper clamp 5 and pinion support plate 9, the shutter plate 11 also moves down and operates to close the open portion between the upper and lower clamps 5, 6.

[0022] As clearly shown in Fig. 8, the link mechanism 7 is supported between the support plate portion 41 and a cover plate 43 fixed to the front side of the support plate portion 41 in parallel with and spaced apart from the support plate portion 41 by bolts 44. As clearly shown in Figs. 4 and 8, the link mechanism 7 includes a generally arc-shaped pulling lever 71 connected to the pulling wire W, and a generally L-shaped push-up lever 72 that rotates to push up the lower clamp 6 when the pulling lever 71 is pulled.

[0023] The pulling lever 71 is connected at one end to the pulling wire W, pivoted to the support plate 41 by a shaft 73 in the middle of the arc-shaped long hole 71a, and pivoted at the other end to one end of the push-up lever 72 by a shaft 74. The push-up lever 72 is pivoted at the middle by a shaft 75 to the link plate 62 of the lower clamp 6, and pivoted at the other end to the support plate 41 by a shaft 76. The pulling lever 71 and the push-up lever 72 are biased by a spring 77 interposed between the shaft 74 and the bolt 44 so as to displace the lower clamp 6 downward.

[0024] As clearly shown in Figure 8, the lower clamp 6 comprises a clamp body 61 and a link plate 62. The clamp body 61 abuts against the underside of the overhead wire G to grip it. A pair of link plates 62 extend downward, sandwiching them at the front and rear of the clamp body 61, and are pivotally attached at their bottoms to the middle part of the push-up lever 72 by a shaft 75.

[0025] The operating rod 3 will be described with reference to Figures 1, 3 and 10. The operating rod 3 is composed of a telescopic pipe consisting of three component tubes, first to third, 31, 32 and 33, which can be mutually extended, retracted and fixed, and is detachably connected to a connecting plate 85 at the tip of the first component tube 31 on the tip side.

[0026] A notched groove 31a is formed at the tip of the first component pipe 31 in a direction perpendicular to the pipe axis to receive the detachment rod 85a, and inside the first component pipe 31, a connection clevis 34 is provided that is biased to a holding position by a spring 35 and that holds the detachment rod 85a perpendicular to the notched groove 31a. The connection clevis 34 is engaged with the base end of the third component pipe 33 by an operation knob 37 via an operation wire 36 that passes through the three component pipes 31, 32, and 33. When the connection clevis 34, which is in the holding position, is pulled to the release position via the operation knob 37 and operation wire 36, the detachment rod 85a is released and the operation rod 3 is disconnected from the transmission mechanism 8.

[0027] A rotary operation handle 39 is connected to the base end of the third component pipe 33 via a torque limiter 38. The rotation of the rotary operation handle 39 is transmitted to the connecting shaft 82 of the transmission mechanism 8 via the operating rod 3 within the range of allowable torque.

[0028] Next, we will explain the wire stringing work using the come-along of the present invention. As shown in Figure 11, with the upper and lower clamps 5 and 6 of the gripping device 2 open, the guide member 53 is hung on the overhead wire G, and the overhead wire G is taken in between the upper and lower clamps 5 and 6 (below the upper clamp 5). In this state, the entire device is supported on the overhead wire G.

[0029] Next, when the operating rod 3 is rotated clockwise around its axis using the rotary operating handle 39 to rotate the threaded rod 52 via the transmission mechanism 8, the threaded rod 52 descends along the threaded cylindrical portion 42 relative to the main body 4 of the gripping device 2, as shown in FIG. 12 . The transmission mechanism 8, pinion support plate 9, and upper clamp 5 are integral with the threaded rod 52, and therefore descend together with the threaded rod 52 relative to the main body 4. Because the clamp main body 51 rests on the overhead wire G, when the upper clamp 5 descends relative to the main body 4, the main body 4, together with the lower clamp 6, is pulled up relative to the overhead wire G. When the main body 4 and the pinion support plate 9 are displaced vertically relative to each other, the pinion gear 10 on the pinion support plate 9 is rotated by the rack 13 fixed to the main body 4, and the shutter plate 11 descends via the rack 12 fixed to the shutter plate 11, closing the side opening between the upper and lower clamps 5 and 6 and preventing derailment of the gripping device 2.

[0030] In this state, while extending the operating rod 3, the gripping device 2 is slid over the overhead wire G to move it to a predetermined position. When the gripping device 2 reaches the predetermined position, the operating rod 3 is further rotated to the right to pull up the lower clamp 6 together with the main body 4, thereby temporarily gripping the overhead wire G between the upper and lower clamps 5 and 6 with an initial gripping force, as shown in Figure 13. When the overhead wire G is gripped between the upper and lower clamps 5 and 6, the rotation operating handle 39 of the operating rod 3 will spin freely due to the torque limiter 38, indicating that temporary gripping has been completed.

[0031] In this state, the operating knob 37 is pulled to remove the connecting clevis 34 from the detachment rod 85a, and the operating rod 3 is removed from the gripping device 2 and collected.

[0032] Next, when the traction wire W connected to the traction lever 71 is pulled toward the pylon T by the chain block C, the push-up lever 72 rotates counterclockwise around the shaft 76 in Figure 13(A) and pushes up the lower clamp 6 via the shaft 75, strengthening the gripping force of the overhead wire G and pulling the overhead wire G toward the pylon T. Until the traction lever 71 is pulled by the traction wire W, the spring 77 urges the push-up lever 72 to rotate clockwise, preventing the lower clamp 6 from rising.

[0033] This completes the wiring work. The tension on the overhead wire G at the construction site is now removed, and the specified construction work can begin.

[0034] Once the required construction work is completed, the chain block C is loosened to reduce the gripping force between the upper and lower clamps 5, 6, and the operating rod 3 is then reconnected to the transmission mechanism 8 of the gripping device 2. The operating knob 37 is pulled to open the notched groove 31a and the detachment rod 85a is inserted into the notched groove 31a, after which the operating knob 37 is returned to engage the connection clevis 34 with the detachment rod and lock it.

[0035] Rotating the rotary operating handle 39 counterclockwise rotates the threaded rod 52 via the transmission mechanism 8, raising the upper clamp 5 relative to the main body 4 and opening the gap between it and the lower clamp 6, releasing the grip on the overhead wire G and releasing the tension. At this time, the rotation of the operating rod 3 is kept to a minimum so as not to open the shutter plate 11. In this state, the operating rod 3 is pulled in to pull the gripping device 2 toward the pylon T. During this time, the shutter plate 11 closes the lateral opening between the upper and lower clamps 5, 6, so the gripping device 2 will not derail from the overhead wire G. Once the gripping device 2 has been pulled in close to the operator, the operating rod 3 is further rotated counterclockwise to pull up the shutter plate 11, and the gripping device 2 is removed from the overhead wire G and recovered. [Explanation of symbols]

[0036] 1 Come Along 2 Gripping device 3 Control stick 31 1st component pipe 31a Notched groove 32 Second component pipe 33 Third component pipe 34 Connecting clevis 35 Spring 36 Control wire 37 Operation knob 38 Torque limiter 39 Rotation control handle 4. Main body of the gripping device 41 Support plate part 411 Rib 42 Threaded barrel 43 Cover plate 44 volts 5 Upper clamp 51 Clamp body 52 Threaded Rod 53 Guide member 6 Lower Clamp 61 Clamp body 62 Link Plate 7 Link mechanism 71 Towing lever 71a Arc-shaped slot 72 Push-up lever 73 axes 74 axes 75 axes 76 axes 77 Spring 8 Transmission Mechanism 81 Gear Case 82 Connecting shaft 82a Pivot pin 83 Bevel gear 84 Bevel gear 85 Connection plate 85a Detachable rod 9 Pinion support plate 91 volts 10 Pinion gear 101 axis 11 Shutter plate 11a long hole 12 racks 121 volts 122 volts 123 Guide groove 13 racks C Chain Block G overhead line I Insulator Ren T-pylon W towing wire

Claims

1. a holding device that is disposed on an overhead wire attached to a steel tower at a position away from the steel tower, holds the overhead wire between upper and lower clamps, and is pulled to the steel tower by a pulling means; and an operating rod connected to the gripping device, which receives the overhead wire between the opened upper and lower clamps, and can slide the gripping device over the overhead wire to an installation position and pull it back, and which remotely controls the gripping device from above the tower by bringing the upper and lower clamps closer together to temporarily grip the overhead wire with an initial gripping force and then separating them to release the grip. The gripping device comprises a main body, the upper clamp supported on the main body so as to be movable up and down relative to the overhead wire, the lower clamp supported on the main body so as to be movable up and down relative to the upper clamp, and a link mechanism supported on the main body, connected to the traction means at one end and connected to the lower clamp at the other end, the upper clamp is configured to descend relative to the main body in conjunction with the rotation of the operating rod around its axis in one direction, temporarily grip the overhead wire between itself and the lower clamp, and to rise and release the grip by the rotation in the other direction, The link mechanism is connected to the lower clamp so as to push up the lower clamp as the pulling means pulls it, thereby gripping the overhead wire between the link mechanism and the upper clamp with a gripping force that is additional to the initial gripping force.

2. A threaded cylindrical portion having an axis extending in the vertical direction is provided on the main body, The upper clamp is connected to a threaded rod that is threadedly engaged with the threaded cylindrical portion and moves up and down, The overhead wire pulling come-along according to claim 1, characterized in that the threaded rod is configured to receive rotation around the axis of the operating rod via a transmission mechanism.

3. A shutter plate is provided on the main body, and moves up and down between an upper open position and a lower closed position in conjunction with the up and down movement of the threaded rod. The overhead wire pulling come-along according to claim 1, characterized in that the shutter plate is configured to open the side opening between the upper and lower clamps in an upper open position to allow the overhead wire to be received between the upper and lower clamps, and to close the side opening in a lower closed position to prevent the holding device from derailing from the overhead wire.

4. The overhead wire pulling come-along according to claim 1, characterized in that the operating rod is composed of a telescopic pipe consisting of a plurality of component tubes that can be extended, retracted, and fixed to each other, and is detachably connected to the gripping device at the tip of the component tube on the tip side.

5. A temporary support method for overhead wire tension using the come-along according to claim 1, a first step of taking the overhead wire between the upper and lower clamps of the holding device in an open state and supporting the holding device on the overhead wire; a second step following the first step of sliding the gripping device on the overhead wire by the operating rod connected to the gripping device to move the gripping device to a predetermined installation position; a third step following the second step of rotating the operating rod in one direction around its axis to lower the upper clamp relative to the main body, thereby temporarily holding the overhead wire between the upper and lower clamps with an initial holding force; a fourth step following the third step, in which one end of the link mechanism is pulled by the pulling means, thereby pushing up the lower clamp and gripping the overhead wire between the lower clamp and the upper clamp with a gripping force added to the initial gripping force, while pulling the overhead wire toward the tower and temporarily supporting it, thereby eliminating tension on the overhead wire at a predetermined construction location; a fifth step of reducing the gripping force between the upper and lower clamps by releasing the traction by the traction means after completion of the work at the predetermined work location; a sixth step following the fifth step of rotating the operating rod connected to the gripping device around its axis in the opposite direction to lift the upper clamp relative to the main body, opening the gap between the upper clamp and the lower clamp, thereby releasing the grip on the overhead wire and releasing tension; A temporary support method for overhead wire tension, characterized in that following the sixth step, it includes a seventh step of pulling the gripping device along the overhead wire to the hand by pulling the operating rod connected to the gripping device and removing it from the overhead wire.

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