JP4122344B2 - Branch line support structure - Google Patents

Description

  The present invention relates to a branch line support structure that holds a branch line from a high-voltage overhead transmission / distribution line on a brace of a utility pole or the like.

  The branch line such as the underline from the high-voltage overhead transmission / distribution line with a nominal voltage of 6600V or less to the primary side of the pole transformer is insulated with a single-core insulated wire (PDC) or ethylene propylene rubber insulated with cross-linked polyethylene. A single-core insulated wire (PDP) is used. The brace provided on the power pole of the high-voltage overhead transmission / distribution line is electrically and mechanically connected to the branch line, and has a built-in current limiting element that protects the transmission / distribution line and other equipment from abnormal voltage caused by lightning surges, etc. An electric wire support insulator is equipped (for example, refer patent document 1).

  The electric wire support insulator is manufactured as an electric wire support insulator having a pin insulator structure in which a current limiting element is incorporated in a hollow insulating insulator. FIG. 9 shows a general wiring form of a high-voltage overhead transmission / distribution line system equipped with such an electric wire support insulator. A pin insulator 4, a current-limiting element-containing electric wire support insulator 5, and a fuse built-in pole transformer protection cutout 6 are fixed to an arm metal 2 installed on the top of the utility pole 1. A lower end portion of a branch line (downline) 11 drawn down from a three-phase three-wire high-voltage overhead transmission / distribution line 10 located at the top of the utility pole 1 is mechanically supported by a pin insulator 4. The branch line 11 drawn out from the pin insulator 4 in the horizontal direction is electrically and mechanically connected to the cutout 6 and the wire support insulator 5 and wired to the pole transformer 3 installed in the utility pole 1. The pole transformer 3 is wired to a three-phase three-wire low-voltage transmission / distribution line 12 of 100 V to 200 V installed on the utility pole 1.

  An example of the electric wire support insulator 5 is shown in FIG. The electric wire support insulator 5 includes a porcelain hollow insulator 5a having insulating properties, and connecting fittings 5b and 5c fixed to both upper and lower ends of the insulator 5a. Hereinafter, the lower connection fitting 5b is referred to as a lower fitting 5b, and the upper connection fitting 5c is referred to as an upper fitting 5c as necessary. The lower metal fitting 5 b is fixed to the arm metal 2, and the wire support insulator 5 is installed on the arm metal 2 upward. The upper metal fitting 5c includes an electric wire gripping portion 5d for electrically and mechanically supporting the horizontal branch line 11 on the top surface. A current limiting element 5e such as ZnO is built in the hollow insulator 5a, and a discharge gap (not shown) is disposed along the side surface of the insulator 5a. The current limiting element 5e is a solid having a non-linear voltage-current characteristic that exhibits a low resistance to surge voltage and a high resistance to the normal ground voltage of the high-voltage transmission and distribution line 10. (Not shown) and the like, and is grounded to the arm metal 2 through the lower metal fitting 5b. In addition, the cutout 6 shown by the chain line in FIG. 10 is a small single-pole switch having a fuse mounted therein, and protects the pole transformer 3.

  When an abnormal voltage due to a lightning surge is generated in the transmission / distribution line 10 due to a lightning strike to the transmission / distribution line 10 or the vicinity thereof, the abnormal voltage is applied to the upper metal fitting 5c of the wire support insulator 5 via the branch line 11, and the discharge gap Is discharged, and the current limiting element 5e cuts off the continuity to prevent the lightning surge from entering the pole transformer 3.

FIG. 11 shows a wiring form of a different high-voltage overhead transmission / distribution line system using the wire support insulator 5. The high-voltage power transmission / distribution line 10 shown in FIG. 11 shows three-phase three-wires, and the branch lines 11 of the three wires are directly and electrically connected to the electric wire support insulator 5. In the case of FIG. 11, three wire support insulators 5 and cutouts 6 corresponding to the three-phase power transmission and distribution wires 10 are fixed to one arm 2 of the utility pole 1. The lower end portion of the branch line 11 suspended from the transmission / distribution electric wire 10 is horizontally bent at a substantially right angle, and this horizontal lower end portion is electrically and mechanically connected to the electric wire gripping portion 5 d of the electric wire support insulator 5.
JP-A-11-251032

  When wind pressure vibration occurs in the high-voltage transmission / distribution line 10, the vibration propagates to the branch line 11, and stress is generated in the branch line 11. This stress mainly acts on the branch line 11 as a tensile force, and when a tensile force due to wind pressure vibration repeatedly acts on the same portion of the branch line 11 over a long period of time, the element wire is easily fatigued due to metal fatigue.

  In the case of the wiring configuration of FIG. 9, the lower end portion of the branch line 11 pulled down from the transmission / distribution line 10 is supported by the pin insulator 4 and connected to the wire support insulator 5 through a short distance from the pin insulator 4. Therefore, the wire holding ability for supporting the branch line 11 is excellent, the electric wire vibration resistance performance by the wind pressure vibration of the transmission / distribution line 10 is good, and even if the wind pressure vibration occurs in the transmission / distribution line 10, the strands of the branch line 11 are Hard to get tired and hard to break. However, in the wiring form of FIG. 9, it is necessary to use a pin insulator dedicated to branch line support in order to support one branch line 11 with higher electric wire gripping ability, and the overall wiring form is complicated and expensive. There is a bug. Moreover, the work which connects the branch line 11 to the pin insulator 4 and the electric wire support insulator 5 by an indirect hot wire method using an aerial work vehicle has many places to connect, and workability | operativity is bad.

  In the case of the wiring form of FIG. 11, since the branch line 11 from the transmission / distribution line 10 is directly supported by the wire support insulator 5, the pin insulator dedicated to the branch line support can be omitted, the wiring form is simplified, and the cost is reduced. Can be. However, since the branch line 11 is directly pulled down from the transmission / distribution line 10 to the wire support insulator 5, the wind pressure vibration of the transmission / distribution line 10 directly affects the entire branch line 11 to connect to the wire support insulator 5. A large tensile force acts on the part. As the branch line 11, an insulated electric wire (PDC or PDP) that is easy to bend with an indirect hot wire tool is used, but a tensile force due to wind pressure vibration of the transmission / distribution electric wire 10 at a substantially bent portion near the electric wire support insulator 5. When repeatedly acts, the wire is fatigued at the bent portion and is easily broken.

  The present invention has been made in view of the problem that the branch line in FIG. 11 is easily disconnected, and the object is to achieve a wiring configuration in which the branch line is less likely to be disconnected than in the wiring configuration in FIG. It is to provide a simple branch line support structure.

The technical means for achieving the above object of the present invention is a branch line support structure that is fixedly arranged on a power pole and holds a branch line from a transmission and distribution line, and the branch line is bent in a U-shape. The wire gripping portion to be gripped is between a pair of left and right linear portions of the U-shaped bent portion and a wire locking surface where the pair of left and right straight portions of the U-shaped bent portion of the branch line abuts on the outside It has a guide surface that guides the semicircular arc part while maintaining its shape, and the U-shaped bent part of the branch line is held by the wire locking surface and the guide surface to fix the branch line temporarily. A member and an I-shaped bracket whose central part is rotatably connected to the fixing member via an elastic member with a connecting bolt, and the both ends are in a posture in which the longitudinal direction is substantially perpendicular to the electric wire to be gripped When the posture extends in the direction parallel to the wire to be gripped, extending to the wire locking surface One end portion so as to protrude from the guide surface, characterized by being constituted by a movable member for fixing by gripping a U-shaped curved portion that is temporarily held by a fixing member in the fixing member.

  Here, the branch line support structure is installed on a metal pole armature or a fixed object such as an insulator or an electric device installed on the armrest, and partially holds the branch line from the high-voltage power distribution line. . The electric wire gripping portion of the branch line support structure is a portion that grips the branch line in a state of being bent in a U shape in the vertical direction, the horizontal direction, or the oblique direction.

  The wire holding surface of the wire gripping portion is two surfaces for gripping and temporarily fixing the pair of left and right straight portions of the U-shaped bent portion of the branch line from the outside, and the left and right sides where the pair of left and right straight portions are fitted together An inner wall surface of a pair of grooves, a stepped surface of a pair of left and right protrusions that are spaced apart and opposed to each other can be applied. The guide surface of the wire gripping portion is a curved surface that guides the U-shaped bent portion of the branch line in a semicircular arc-shaped state, and the elastic recovery of the U-shaped bent portion along the curved portion. The straight portion of the branch line is pressed against and locked to the wire locking surface by the force. The guide surface can be formed by one surface or a pair of left and right surfaces.

  As the fixing member here, a T-shaped metal fitting can be applied as viewed from the front side integrally protruding on the upper metal fitting. By positioning and temporarily holding the U-shaped bent portion of the branch line between the wire locking surface and the guide surface of the fixing member, it is easy to attach the branch line to the branch line support structure by the indirect hot wire method. The movable member can be an I-shaped bracket attached to the front side of a fixed member that is a T-shaped bracket. A connecting bolt is inserted into the central portion of the movable member, the connecting bolt is screwed into the central portion of the fixing member, which is a T-shaped bracket, and the movable member is attached to the front surface of the fixing member so as to be rotatable around the connecting bolt. . A connecting bolt having a hexagonal head that is easy to work with an indirect hot wire tool is desirable for facilitating indirect hot wire work. In addition, when the I-shaped movable member does not grasp the electric wire (branch line) to be grasped, the movable member is rotated so that one end portion thereof protrudes from the guide surface of the fixed member. By doing in this way, when the branch line fitted in the guide surface unintentionally tries to come out of the guide surface, it comes into contact with one end portion of the movable member protruding from the guide surface and is prevented from coming out. By providing the movable member with a stopper function that prevents the branch line from coming out in this way, the temporary holding of the branch line bent portion by the fixed member is stabilized, and the electric wire mounting work by the indirect hot wire method is easier. Become.

  Furthermore, in the present invention, an elastic member that urges the connecting bolt in the axial direction can be interposed between the movable member of the wire gripping portion and the head of the connecting bolt. This elastic member is a coil spring, disk spring, etc. When the connecting bolt is loosened with an indirect hot wire tool, the movable member is prevented from moving freely with respect to the fixed member, and work using the indirect hot wire tool is performed. Make it easy to do.

  Moreover, in this invention, the electric wire holding part in a branch line support structure can be provided in the electric wire support insulator installed in the armrest of a utility pole. Furthermore, the electric wire gripping part in the branch line support structure can be provided in a connection fitting that is electrically and mechanically connected to the branch line of the current limiting element built-in type electric wire support insulator installed in the armrest of the utility pole.

  Here, as the electric wire support insulator, a pin insulator provided with a solid insulating insulator or an insulator in which a current limiting element or the like is incorporated in a hollow insulating insulator can be applied. As the hollow insulator incorporating the current limiting element, a ceramic insulator, a resin insulator, or a fiber reinforced resin insulator in which glass fibers or ceramic fibers are dispersed can be applied. Further, as the resin insulator, EVA resin (preferably fiber reinforced EVA resin) insulator, silicone resin (preferably fiber reinforced silicone resin) insulator, epoxy resin (preferably fiber reinforced epoxy resin) insulator can be applied.

  In the current limiting element built-in type electric wire support insulator equipped with the branch line support structure, the connection fitting fixed to one end of the insulator is fixed to the arm of the electric pole and grounded. An electric wire gripping part is integrally installed on a connection fitting fixed to the other end of the insulator, and a bent part bent into a substantially U-shape of a branch line from a high-voltage transmission / distribution line is electrically connected to the electric wire gripping part. And mechanically supported. The U-shaped bent portion of the branch line is bent by an indirect hot wire tool when the branch wire is connected to the electric wire support insulator, is directly inserted into the electric wire gripping portion, and is fixed by an appropriate means such as bolting. . The U-shaped bent portion of the branch line supported by the wire gripping portion is formed by a pair of left and right straight portions facing each other and a semicircular arc portion therebetween, and one of the pair of left and right straight portions is on the high-voltage transmission and distribution line side. The other straight line portion is connected to a pole transformer protection cutout or the like. The tensile force acts on the straight line part of the U-shaped bent portion of the branch line due to the wind pressure vibration of the high-voltage transmission line, but this tensile force acts in the axial direction of the straight part. The damage to the branch line is small. Therefore, the U-shaped bent portion of the branch line is excellent in wire vibration resistance against wind pressure vibration of the transmission / distribution line. This electric wire vibration resistance performance is comparable to or higher than that of the branch line in the wiring configuration of FIG.

  Further, in the present invention, the one end of the movable member of the electric wire gripping part is screwed with a cutting edge bolt that can be electrically connected to the branch line through only the insulating coating, and the electric wire holding part of the electric wire support insulator. The cutting edge bolt can be electrically connected to the straight portion on the opposite side, not the straight portion from the transmission / distribution line, of the pair of left and right straight portions of the U-shaped branch line bending portion supported by the wire.

  A commercial item can be applied to the blade bolt here. This cutting edge bolt is a pair of left and right straight portions of the U-shaped branch wire bent portion supported by the wire gripping portion of the wire support insulator, and can be electrically connected to the straight portion from the transmission and distribution line. It is more effective to make the electrical connection only to one straight line part on the opposite side of the straight line part from the distribution line in order to lessen the influence of mechanical damage etc. to the branch line due to vibration from the transmission line. is there.

Further, in the present invention, conductive lines gripper and the electric wire in a U-shaped branch line curved portion which is supported by the grip portion is deposited detachably insulating cover, U-shaped branch line the bent in the insulating cover A linear extension extending from the straight portion of the part can be retained.

  As the insulating cover here, a resin molded product having a bivalve structure can be applied. The insulating cover insulates and protects the charging portion of the wire support insulator as in the conventional case, and grips and supports the linear portion extension portion extending from the wire gripping portion of the U-shaped branch line bending portion supported by the wire gripping portion. . Therefore, the wire gripping ability of the branch line from the high-voltage transmission / distribution line is increased, and the wire vibration resistance performance due to the wind pressure vibration of the transmission / distribution line is further improved.

  Further, in the case of the present invention, a plurality of electric wire support insulators are installed on the same arm of the electric pole, and the heads of the respective connecting bolts and cutting edge bolts of all the plural electric wire support insulators are arranged in the same direction. Each branch line extending in the direction opposite to the transmission / distribution line side from all the plurality of wire support insulators can be wired to the pole transformer installed on the above-mentioned utility pole.

  By installing a plurality of wire support insulators on one arm of a single utility pole and directing the heads of connecting bolts and cutting edge bolts provided on the wire gripping portions of all the plurality of wire support insulators in the same direction In addition, the wiring form of the electric wire support insulator becomes compact, and the indirect hot-wire work of electric wire attachment using an aerial work vehicle becomes easy and can be performed more safely.

  According to the present invention, the branch line from the transmission / distribution line is directly routed to the branch line support structure installed on the armrest of the utility pole, and the electric wire gripping of the branch line support structure is performed in a U-shaped state. Because the wind pressure vibration of the transmission / distribution line propagates from the branch line to the wire gripping part and a tensile force acts on the branch line, this tensile force is applied to one of the U-shaped bent parts of the branch line. It is possible to exert an excellent effect that the wire vibration resistance performance against the wind pressure vibration of the transmission / distribution line is increased. Moreover, by providing a branch line support structure on the electric wire support insulator of the utility pole, the branch line can be directly connected to the electric wire support insulator from the high-voltage transmission / distribution line, and the wiring form between the transmission / distribution line and the electric wire support insulator Is simplified, and indirect hot-line work at high places can be performed with less man-hours and high efficiency.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  1 to 7 show an embodiment of a wire support insulator 20 equipped with a branch line support structure, and FIG. 8 shows a wiring configuration of a high-voltage overhead transmission and distribution line system using the wire support insulator 20. FIG. 8 is applied to the same wiring form as FIG. 11, and the same or corresponding parts as those in FIG.

  An electric wire support insulator 20 shown in FIG. 1 is a current limiting element built-in type standing on an arm metal 2. A lower metal fitting 22 is fixed to a lower part of an insulating hollow insulator 21, and an upper metal fitting 23 of a connection metal fitting is fixed to an upper part. The The current limiting element 24 is sealed together with the electrodes in the insulator 21, and a discharge gap 25 is formed on the side of the insulator 21. The lower metal fitting 22 is fixed to the arm metal 2. The upper metal fitting 23 is integrally provided with a wire gripping portion 30 as a branch wire support structure that attaches and detaches the branch wire 11 on the top surface and supports it electrically and mechanically. The portion of the wire support insulator 20 excluding the wire gripping portion 30 may have the same structure as the conventional product in FIG. As shown by a chain line in FIG. 1, a resin insulating cover 50 is detachably attached to the upper portion of the wire support insulator 20.

  The electric wire gripping part 30 constituting the branch line support structure detachably supports the lower end part of the branch line 11 hanging from the high-voltage transmission / distribution line 10 in a U-shaped state. The wire gripping portion 30 includes a T-shaped bracket fixing member 31 fixed to the upper bracket 23, a I-shaped bracket movable member 32 connected to the fixing member 31 so as to be rotatable in the vertical direction, and a movable member. A connecting bolt 33 that movably connects 32 to the fixing member 31 is provided. The fixed member 31 is temporarily held in a state where the lower end portion of the branch line 11 hanging from the transmission / distribution line 10 is bent in a U shape, and the movable member 32 is a U shape of the branch line 11 temporarily held by the fixed member 31. The bent portion 11a is pressed and fixed to the fixing member 31. A cutting edge bolt 34 that penetrates only the insulating coating of the branch line 11 of the insulated wire and is in electrical contact with the element wire is screwed to one end of the movable member 32.

  The U-shaped bent portion 11a of the branch line 11 supported by the wire gripping portion 30 includes a pair of left and right straight portions 11b facing each other at a predetermined interval and a semicircular portion 11c of a downward arc between the pair of left and right straight portions 11b. Formed with. The branch wire 11 is an insulated wire (PDC or PDP) that is easily bent by an indirect hot wire tool (not shown), and the bent portion 11a is bent by using the indirect hot wire tool, and the fixing member 31 of the wire gripping portion 30 is used. Are fixed on the movable member 32 after temporarily being positioned and temporarily held.

  Specific examples of the fixed member 31 and the movable member 32 are shown in FIGS.

  The fixing member 31 of the T-shaped bracket has a pair of guide grooves 41a and 41b on the front surfaces of both ends of the horizontal portion at the upper end. The guide grooves 41a and 41b are portions where the pair of right and left straight portions 11b and 11b of the U-shaped bent portion 11a of the branch line 11 are temporarily held, and the guide grooves 41a and 41b are branched. It has the same width as the diameter of the line 11 and has a depth slightly larger than the diameter of the branch line 11. As shown in FIG. 7A, the edges of the guide grooves 41a and 41b are finished to be curved by chamfering. By making such an edge portion a curved surface, the degree of bending in the vicinity of the groove edge portion when the branch line 11 is shaken in a state of being fitted into the guide grooves 41a and 41b is compared with a case where chamfering is not performed. It is relieved greatly, and the risk of wire breakage is greatly reduced. The outer inner wall surfaces of the guide grooves 41a and 41b are formed as electric wire locking surfaces 42 and 42 with which the pair of left and right straight portions 11b and 11b of the branch line 11 are elastically contacted on the outer side.

  The fixing member 31 of the T-shaped metal fitting has a step-shaped guide surface 43 on the front surface of the I-shaped central portion. The guide surface 43 is a portion that guides the semicircular arc portion 11c and holds it in a semicircular arc shape when the semicircular arc portion 11c of the branch line bending portion 11 is disposed along the guide surface 43. For example, a pair of protrusions 44 project from the left and right sides of the front surface of the I-shaped central portion of the fixing member 31, and curved guide surfaces 43 are formed on the outer and lower surfaces of each protrusion 44. Each protrusion 44 protrudes from the front surface of the I-shaped central portion of the fixing member 31 with a length slightly larger than the diameter of the branch line 11.

  The movable member 32 of the I-shaped bracket is a horizontally long plate-shaped stopper that is attached to the front surface of the upper horizontal portion of the fixing member 31 of the T-shaped bracket. The connecting bolt 33 is inserted through the central portion of the movable member 32 through an elastic member 35 such as a coil spring, and the connecting bolt 33 is screwed into the central portion of the fixing member 31 of the T-shaped bracket. A cutting edge bolt 34 is screwed to one end of the movable member 32. The movable member 32 can rotate up and down around the connecting bolt 33 on the front surface of the fixed member 31. Both end portions of the movable member 32 are set to be spaced apart from the pair of left and right guide grooves 41 a and 41 b of the fixed member 31. At the end opposite to the one end where the cutting edge bolt 34 of the movable member 32 is attached, an electric wire presser projection 36 is provided which slightly enters the opening of the guide groove when this end faces either of the guide grooves 41a, 41b. Is done. Each of the connecting bolt 33 and the cutting edge bolt 34 has a hexagonal head that can be easily bolted and loosened with an indirect hot wire tool. As shown in the exploded view of FIG. 5, the connecting bolt 33 is attached to the movable member 32 via an elastic member 35, for example, a disc spring 35a and a coil spring 35b. The elastic member 35 always urges the connecting bolt 33 in the axial direction to prevent the movable member 32 from rotating unintentionally during the bolt loosening operation, thereby facilitating the indirect hot wire operation. The cutting edge bolt 34 is screwed into the movable member 32 via the spring washer 37 a and the flat washer 37 b, and the cutting edge protrudes from the movable member 32.

  7A and 7B, when the movable member 32 is rotated vertically on the front surface of the fixed member 31, the lower end portion of the guide surface 43 on the front surface of the center portion of the fixed member 31 is formed. The total length of the movable member 32 is determined so as to project near the front. The lower end portion of the movable member 32 forms a gap in which the branch line 11 can be fitted with the guide surface 43. Further, the lower end portion of the movable member 32 is locked when the branch line 11 fitted in the guide surface 43 tries to escape forward from the guide surface 43, and prevents the branch line 11 from being unintentionally pulled forward. It functions as a stopper.

  The branch wire 11 is attached to the wire gripping portion 30 of the wire support insulator 20 by the indirect hot wire method as follows. When the wire support insulator 20 is in the state shown in FIG. 6 on the armrest 2 of the utility pole 1, the worker gets on the bucket of an aerial work vehicle, approaches the wire support insulator 20, and is attached to the end of a long insulating rod (not shown). The connecting bolt 33 is loosened with an indirect hot wire tool dedicated to the bolt, and the horizontal movable member 32 is rotated by 90 ° as shown in FIG. The lower end portion of the movable member 32 that is rotated 90 ° from the horizontal posture to have a vertically long vertical posture projects over the guide surface 43 of the fixed member 31. Next, the operator grips two spaced apart portions of the lower end portion of the branch line 11 hanging from the high-voltage transmission / distribution line 10 with an indirect hot wire tool, and curls the branch line 11 between the tools in a U shape. The bent portion 11a is inserted into the guide grooves 41a and 41b of the fixing member 31 and temporarily held. Specifically, the pair of left and right linear portions 11b of the bent portion 11a is fitted into the corresponding pair of left and right guide grooves 41a and 41b with the semicircular arc portion 11c of the bent portion 11a being along the guide surface 43. The electric wire insertion operation using the indirect hot wire tool can be accurately and easily performed because the lower end portion of the movable member 32 in the vertical posture prevents the bent portion 11a from coming off from the guide surface 43. When the indirect hot wire tool is removed from the bent portion 11a, the pair of left and right linear portions 11b are deformed to be separated from each other by the elastic restoring force of the bent portion 11a, and the outer inner wall surfaces of the corresponding guide grooves 41a and 41b, respectively. The bent portions 11a are temporarily held in a stable posture while being kept in a U shape along the guide surface 43 by the pressing force.

  Next, the worker rotates the movable member 32 in the vertical posture by 90 ° to the horizontal posture using an indirect hot wire tool. When the movable member 32 returns to the horizontal posture, both ends are positioned at the openings of the pair of left and right guide grooves 41a and 41b, and the wire holding protrusion 36 at one end is connected to the branch line 11 of the insulated wire fitted into one guide groove 41a. The blade tip of the blade bolt 34 at the other end approaches and approaches the lead wire 11 fitted in the other guide groove 41b. In this state, when the connecting bolt 33 is tightened with an indirect hot wire tool and the movable member 32 is tightened toward the fixed member 31, the wire pressing protrusion 36 at one end of the movable member 32 is formed in the guide groove 41a as shown in FIG. One straight portion 11b of the branch line 11 is pressed and fixed to the guide groove 41a, and the blade bolt 34 at the other end pierces the insulation coating of the other straight portion 11b of the branch line 11 of the guide groove 41b. When the cutting edge bolt 34 is tightened with an indirect hot wire tool, the cutting edge penetrates only the insulating coating of the straight portion 11b and makes electrical contact with the element wire. If the heads of the cutting edge bolt 34 and the connecting bolt 33 are unified into a hexagonal head of the same size, the worker uses an indirect hot wire tool dedicated to one type of bolt to perform bolting and loosening of the bolt in order. It is convenient to do.

  Further, as shown in FIG. 8, three wire support insulators 20 corresponding to the three-phase three-wire high-voltage transmission / distribution wires 10 are installed on one arm 2 of the utility pole 1, and the respective connecting bolts 33 and cutting edges are provided. If the bolts 34 are pointed in the same direction on the front side in FIG. 8, the worker can perform an indirect hot-line operation of each bolt from the same direction on the front side in FIG. In other words, the indirect hot work at high places can be performed quickly and safely without moving the work place at high places.

  As shown in FIG. 1, the U-shaped bent portion 11 a of the branch wire 11 supported by the wire gripping portion 30 of the wire support insulator 20 has a high wire vibration resistance against the wind pressure vibration of the transmission and distribution wire 10. . The tensile force applied to the branch line 11 acting by the wind pressure vibration of the power transmission / distribution line 10 acts on one straight line portion 11b of the U-shaped branch line bent portion 11a in the axial direction. Is pulled upward, the semicircular arc portion 11 c is engaged with the guide surface 43 of the fixing member 31. Further, the branch line 11 from the straight-line portion 11b on the opposite side to the transmission / distribution line side of the bent portion 11a to the cut-out 6 is short and is not easily affected by the wind pressure vibration of the transmission / distribution line 10 originally. . Therefore, the wire gripping ability of the wire gripping portion 30 with respect to the wind pressure vibration of the transmission / distribution line 10 is high, and the wire vibration resistance performance of the branch line 11 against the wind pressure vibration of the transmission / distribution line 10 is high. It has been verified that the electric wire vibration resistance is comparable to or higher than the electric wire vibration performance in the wiring configuration of FIG. For example, in the vibration test up to the disconnection using the PDC for the branch line 11, the number of vibrations until the disconnection in the wiring configuration of FIG. 9 and FIG. 8 is almost the same, and up to the disconnection when the PDP is used for the branch line 11. The number of vibrations is 3-4% better in the wiring configuration of FIG. 8 than in the wiring configuration of FIG.

  The vibration resistance performance of the branch line 11 against the wind pressure vibration of the transmission / distribution electric wire 10 becomes even better and more stable when the insulating cover 50 is mounted on the upper portion of the electric wire support insulator 20. This insulating cover 50 is a resin-molded product having a bivalve structure made of flame-retardant polyethylene. As shown by a chain line in FIG. 3, the insulating cover 50 is configured by connecting two halves 51, 52 so that they can be opened and closed by one hinge portion 55. Handles 53 and 54 project from the two halves 51 and 52, respectively, and the grips 53 and 54 are held by an indirect hot wire tool to open the halves 51 and 52, and are moved to the upper part of the wire support insulator 20. By closing, the insulating cover 50 is mounted. The insulating cover 50 includes a pair of left and right straight portions 11b of the U-shaped branch line bending portion 11a extending upward from the wire gripping portion 30 of the wire support insulator 20, and an extending portion extending upward from the straight portion 11b. Grip and hold at the top of each half 51, 52. Therefore, the wire vibration resistance performance against the wind pressure vibration of the high-voltage transmission / distribution line 10 is increased by the reinforcing effect of the insulating cover 50, and the branch line 11 is hardly further broken.

  The anti-wire vibration performance of the branch line 11 against the wind pressure vibration of the high-voltage transmission / distribution line 10 was verified by tensile compression vibration and rotational vibration. As a result, when the PDP is used for the branch line 11, the number of vibrations until the branch line breaks is improved by 7 times for the vibration vibration and 1.5 times for the tension compression vibration by attaching the insulating cover 50. Verified. In addition, when PDC is used for the branch line 11, the number of vibrations until the branch line breaks is about 4 times the rotational vibration and about 1.2 times the tensile compression vibration by attaching the insulating cover 50. Was verified.

  In addition, the electric wire support insulator 20 installed on the armrest 2 of the utility pole 1 is not suitable for construction or electrical insulation unless the wiring of the high voltage transmission / distribution electric wire side and the high voltage cutout side is changed depending on the facility location ( (Distance between lines and ground)). In such a case, for example, the position of the cutting edge bolt 34 may be changed by rotating the movable member 32 in the vertical posture of the wire gripping portion 30 of FIG. 7 by 90 ° counterclockwise in FIG. Further, the movable member 32 can be rotated at an angle of 180 ° or more with respect to the fixed member 31 so that the position of the blade bolt 34 can be changed by 180 °.

  The above embodiment is applied to the wiring form of the wire support insulator suspended from the branch line (downline) pulled down from the high-voltage transmission / distribution line and the arm of the utility pole. The present invention is not limited to such a wiring form and can be applied. For example, in a state where the branch line from the high-voltage transmission / distribution line is drawn from the horizontal direction or the oblique direction into the electric wire support insulator installed in the horizontal specification or the oblique installation specification on the arm of the electric pole and bent in a U shape. The electromechanical connection can be made in the same manner as in the embodiment.

It is a front view containing the partial cross section of the electric wire support insulator which shows embodiment of this invention. It is a front view of the part which mounted | wore with the insulation cover of the electric wire support insulator of FIG. It is a top view of the part of FIG. It is an enlarged plan view including the partial cross section of the electric wire holding part of the electric wire support insulator of FIG. It is an exploded view of the electric wire holding part of FIG. (A) And (B) is the front view and side view of an electric wire holding part of FIG. (A) And (B) is the front view and side view at the time of operation | movement of the electric wire holding part of FIG. It is a layout for demonstrating the wiring form of the high voltage | pressure overhead transmission / distribution electric wire system which attached the electric wire support insulator of FIG. 1 to the utility pole. It is a layout for demonstrating the general wiring form of the high voltage | pressure overhead transmission / distribution system equipped with the conventional electric wire support insulator. It is a front view which shows the outline | summary of the conventional electric wire support insulator. It is a layout for demonstrating an example of the wiring form of the high voltage | pressure overhead transmission / distribution electric wire system which attached the electric wire support insulator of FIG. 10 to the utility pole.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Telephone pole 2 Arm metal 3 Pole transformer 6 Cutout 10 Transmission / distribution electric wire 11 Branch line 11a U-shaped bending part 11b Straight line part 11c Semicircular arc part 20 Electric wire support insulator 21 Insulator 22 Connection metal fitting, Lower metal fitting 23 Connection metal fitting, Upper metal fitting 24 Current limiting element 25 Discharge gap 30 Electric wire gripping portion 31 Fixed member 32 Movable member 33 Connecting bolt 34 Cutting edge bolt 35 Elastic member 42 Electric wire locking surface 43 Guide surface 44 Protruding portion 50 Insulating cover

Claims (3)

A branch line support structure that is fixedly installed on a power pole and holds a branch line from a transmission and distribution line,
An electric wire gripper that grips the branch line in a U-shaped state ,
An electric wire locking surface on which the pair of left and right straight portions of the U-shaped bent portion of the branch line abuts on the outside thereof, and a semicircular arc portion between the pair of left and right straight portions of the U-shaped bent portion are A fixing member that has a guide surface that guides the shape in a substantially maintained state, and that temporarily holds the branch line by retaining the U-shaped bent portion of the branch line by the wire locking surface and the guide surface;
A center part is an I-shaped bracket that is rotatably connected to the fixing member via an elastic member with a connecting bolt, and both ends are in the posture in a direction in which the longitudinal direction is substantially perpendicular to the electric wire to be gripped. A U-shaped curve that extends to the locking surface and that has one end projecting from the guide surface when the longitudinal direction is substantially parallel to the wire to be gripped, and is temporarily held by the fixing member A movable member that grips and fixes the formed part with a fixed member;
The branch line support structure characterized by comprising. A cutting edge bolt capable of being electrically connected through only the insulation coating is screwed into one end portion of the movable member in the electric wire gripping portion, and the cutting edge bolt is supported by the electric wire gripping portion. in a pair of left and right linear portions of the U-shaped branch line curved portion, branch line support according to claim 1, characterized in that electrically connected to the linear portion on the opposite side straight portion of the electric transmission Structure. An insulating cover is detachably attached to the wire gripping portion and the U-shaped branch line bent portion supported by the wire gripping portion, and the straight portion of the U-shaped branch wire bent portion is covered with the insulating cover. The branch line support structure according to claim 1 or 2 , wherein a linear extension portion is held.

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