JP3329792B2 - Cable connection part and cable extraction method using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable connecting portion and a cable extracting method using the same, and more particularly, to a connecting portion between a cable conductor and an internal conductor forming a bushing (hereinafter, referred to as an "energizing portion"). More particularly, the present invention relates to a cable connecting portion provided with means for restraining and retaining a cable conductor itself, and a cable extracting method using the same.

2. Description of the Related Art In general, at a terminal connection portion of a power cable, in addition to a function of flowing a current flowing through a cable conductor to an inner conductor of a bushing (hereinafter referred to as an "energizing function"), the cable conductor is used as an inner conductor of the bushing. A restraining and retaining function (hereinafter referred to as “retaining function”) is also required. Conventionally, as a terminal connection portion of a power cable having such an energizing function and a termination function, a cylindrical wedge having a slit in an axial direction on an outer periphery of a distal end portion of a cable conductor, and a cylindrical shape having a screw portion on an outer periphery. The wedge fastener is mounted with the wedge arranged at the upper part, and the screw part of the wedge fastener is screwed into the screw part formed on the inner peripheral surface of the inner conductor of the bushing. A wedge fastening method is known in which a wedge is fixed to the outer peripheral surface of a cable conductor by screwing the wedge toward the cable conductor. However, in the terminal connection portion of the power cable using the wedge tightening method, a wedge tightening bracket is disposed below the wedge, and a wedge tightening tool is further disposed below the wedge tightening bracket. Since the wedge fastener must be rotated, when incorporating the wedge and the wedge fastener (hereinafter referred to as “current-carrying parts”), the pre-molded insulator attached to the outer periphery of the cable insulation layer must be positioned below. There is a drawback in that the cable sheath must be lowered, and the cable sheath must be removed more than necessary as the pre-mold insulator is lowered. In addition, as a result of removing the cable sheath more than necessary, after assembly of the current-carrying parts, the cable protection fitting for protecting the removed portion of the cable sheath becomes longer, and the entire terminal connection portion of the power cable becomes larger. was there. Furthermore, the bushing may be damaged by the wedge tightening tool used when assembling the current-carrying parts, and the cutout generated when the wedge tightening screw is screwed remains in the inner part of the bushing, and as a result, the power cable There is a possibility that the insulation characteristics at the terminal connection part of the above may be degraded. For this reason, in order to reduce the size of the current-carrying portion, save labor for assembling the current-carrying parts, and improve the insulation characteristics at the terminal connection portion of the power cable, a terminal connection portion of a power cable using a so-called ball lock method has been developed. I have. FIG. 4 is a longitudinal sectional view of a main part of a terminal connection portion of a power cable using such a ball lock system.
In the figure, the terminal connection portion of the power cable is fitted with a bottomed cylindrical internal plug 2 compression-connected to the outer periphery of the upper end portion of the cable conductor 1 and the outer periphery of the internal plug 2.
A cylindrical external plug 4 that conducts between a bottomed cylindrical internal conductor 3 and an internal plug 2 that constitutes a bushing (not shown); and a shaft of the external plug 4 at a lower portion of the inner peripheral surface of the external plug 4. Metal fittings 5 movably arranged in the direction, and pressed by the metal fittings 5, project into the ball storage grooves 3 a formed on the inner peripheral surface of the internal conductor 3, and extend between the external plug 4 and the internal conductor 3. And a coiled spring 7 disposed between the external plug 4 and the press fitting 5. The above-mentioned press fitting 5 is provided with a cable insulating layer 8.
An annular pressing member 5a that is pressed when the pre-mold insulator 9 fitted to the outer periphery of the upper end of the mounting member is mounted at a predetermined position;
A projecting member 5b is provided for projecting the ball 6 into the ball storage groove 3a of the internal conductor 3 when the pressing fitting 5 advances to the bushing side by this pressing. The upper end of the coiled spring 7 is fitted in an annular groove 4a provided on the lower surface side of the external plug 4, and the lower end is fitted in an annular spring storage groove 5c provided on the upper side of the press fitting 5. It is stored. Reference numeral 1a designates a wedge which is driven from the screw hole 2b side provided in the bottom 2a of the internal plug 2 to the distal end of the cable conductor 1, 4c designates a flange protruding from the inner periphery of the upper end of the external plug 4, and 10 designates a lower surface. A disk-shaped connecting member having a boss portion 10a at the center thereof is a threaded portion formed on the outer periphery of the boss portion 10a, and 2c and 4b are annular concave grooves formed on the outer periphery of the inner plug 2 and the outer plug 4 respectively. The conductor connectors respectively mounted are shown. When the pre-mold insulator 9 is pressed to the bushing side by a pressing mechanism (not shown) at the terminal connection portion of the power cable having such a configuration, the pre-mold insulator 9 is disposed at the upper end portion. The formed annular stopper 9a comes into contact with the pressing member 5a and pushes the pressing metal 5 upward. And the projecting member 5b
The ball 6 supported on the inclined surface is pushed up to the top of the protruding member 5b by the inclined surface, and a part of the ball 6 projects into the ball storage groove 3a and the movement of the ball 6 inward in the radial direction is projected. Blocked by member 5b. As a result, the inner conductor 3 and the outer plug 4 are locked, and the flange portion 4c of the outer plug 4 is
Since the internal plug 2 is fixed to the cable conductor 1, the cable is prevented from falling off. Next, a method of pulling out the cable from the bushing at the terminal connection portion of the power cable having such a configuration will be described. First, a cable protection bracket (not shown) surrounding the outer periphery of the cable terminal is removed to expose the cable terminal. Next, a drawing tool (not shown) is attached to the outer periphery of the pre-mold insulator 9, and the pre-mold insulator 9 is pulled down by about 5 to 10 mm. Then, since the stopper 9a retreats downward, the pressing fitting 5 is lowered by receiving the spring force of the spring 7, the restraint of the ball 6 is released, and the ball 6 moves radially inward as shown in FIG. . As a result, the lock of the external plug 4 is released, and thus the lock of the cable conductor 1 is released, so that the cable can be pulled out from the bushing. According to the terminal connection portion of the power cable having such a configuration, it is not necessary to dispose a wedge fastener below the wedge, so that the current-carrying part can be reduced in size and the wedge fastener can be reduced. Since it is not necessary to dispose a wedge tightening tool at the lower part of the part, labor for assembling the energized part can be saved, and the energized parts can be assembled without using a wedge tightening tool. In addition, no cut pieces are generated when the current-carrying parts are assembled, and the insulation characteristics at the terminal connection of the power cable can be improved.

However, in the terminal connection portion of the power cable using such a ball lock system, it is easy to replace the pre-mold insulator at the time of switching the power cable line or the like. There was a drawback that you could not. In other words, at the terminal connection portion of the power cable including the pre-molded insulator on the outer periphery of the cable insulating layer, the pre-molded insulator is fixed to the outer periphery of the cable insulating layer by use for several months to several years after the start of operation. There is a drawback in that it requires a great deal of labor to pull this downward along the outer peripheral surface of the cable insulating layer by human power. Further, there is a case where the lowering of the pre-molded insulator is accompanied by the dismantling of the pre-molded insulator, and as a result, the pre-molded insulator cannot be reused. The present invention has been made in order to solve the above-mentioned difficulties, and is a cable connection capable of reducing the size of a current-carrying portion, saving labor for assembling a current-carrying part, and improving insulation characteristics at a terminal connection portion of a power cable. Cable pull-out that can provide easy access to the cable from the bushing without providing a part and without undue effort and without damaging the pre-molded insulation, and thus allowing the pre-molded insulation to be reused It is intended to provide a way.

In order to achieve the above object, a cable connecting portion according to the present invention comprises a cylindrical wedge fixed to an outer periphery of an upper end portion of a cable conductor exposed by stripping a cable terminal. A cylindrical retention unit fitted on the outer periphery of the wedge and having locking means, and a conduction member for conducting between the wedge and the cylindrical inner conductor constituting the bushing. Is locked to the inner peripheral surface of the inner conductor by a lock means, and the inner side is movably locked in the axial direction of the wedge on the outer peripheral surface of the wedge. In the present invention,
The wedge is preferably formed of a metal sleeve that expands and contracts in the radial direction, and a conductive member formed of a cylindrical metal plug is preferably pressed into the outer periphery of the upper half of the metal sleeve. Furthermore,
It is preferable that tapered portions are formed on the outer peripheral surface of the upper half portion of the wedge and on the inner peripheral surface of the conductive member so as to reduce the diameter at the same inclination from the lower end to the upper end. According to these inventions, similarly to the above-described terminal connection portion of the power cable using the so-called ball lock system, the energization portion can be reduced in size,
It is possible to save labor for assembling the current-carrying parts and to improve the insulation characteristics at the cable connection part. The cable pulling method of the present invention is characterized in that the cable near the cable terminal is gripped, moved upward by a predetermined length, then pulled back a predetermined length to release the lock, and then the cable is pulled out. ADVANTAGE OF THE INVENTION According to the cable extraction method of this invention, a cable can be easily pulled out from a bushing, without requiring much effort, and without damaging a premold insulator, and reuse a premold insulator. be able to.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a cable connecting portion and a cable extracting method using the same according to the present invention will be described below with reference to the drawings. First, the cable connection part of the present invention will be described. FIG. 1 is a longitudinal sectional view of a cable connecting portion of the present invention, and FIG. 2 is a half cut assembly view of a cable conductor restraining unit of the present invention. In FIG. 1, parts common to FIGS. 4 and 5 are denoted by the same reference numerals. In FIG. 1, the cable connecting portion of the present invention is a crosslinked polyethylene insulated polyvinyl chloride sheath cable of 22 to 66 kV class. (Hereinafter, referred to as “CV cable”). The cable terminal 11 is provided with a cable shielding layer 12 and a cable external semiconductive layer 1 by stripping.
3. The cable insulation layer 8 and the cable conductor 1 are exposed. Thus, a cylindrical wedge 14 is fitted around the outer periphery of the exposed upper end portion of the cable conductor 1, and the wedge 14
A retention unit 15 is fitted around the lower half outer periphery, and a cylindrical conductive member 16 is press fitted into the upper half outer periphery. As shown in FIG. 2, the wedge 14 is formed of a cylindrical metal sleeve, and an annular projection 14a is provided on the outer periphery slightly below the center of the sleeve. Also, wedge 14
The outer periphery of the upper half is formed with a tapered portion 14b whose diameter is reduced from the annular projection 14a toward the upper end, and the outer periphery of the lower half is provided with an annular locking groove 14 connected to the lower end surface of the annular projection 14a.
c is formed. Further, in the upper half and the lower half of the wedge 14, a plurality (for example, eight) of slits 14d and 14e are formed along the axial direction from the upper and lower ends of the wedge 14 to positions near the annular projection 14a, respectively. Each of the slits 14d is formed evenly along the circumferential direction.
Due to the formation of 14e, the wedge 14 itself can be expanded and contracted in the radial direction. A spiral groove (not shown) is formed on the inner periphery of the upper half of the wedge 14, if necessary.
The conductive member 16 is formed of a cylindrical metal plug, and has an inner peripheral surface formed with a tapered portion 16a whose diameter decreases from a lower end toward an upper end. In addition, the conductive member 1
6, a shallow annular groove 16b is formed in the center of the outer peripheral surface, and a tape-shaped conductor connector 16c (for example, a multi-contact (trade name)) that expands and contracts in the thickness direction is formed in the groove 16b. It is mounted along the circumferential direction. The inclination (for example, in the range of 1 to 6 degrees) of the tapered portion 16 a of the conductive member 16 is the same as the inclination of the tapered portion 14 b of the wedge 14. The conductive member 16 having such a configuration is provided with the wedge 14.
Is pressed into the outer periphery of the wedge 14 so as to slide downward from the upper end side, and the wedge 14 is radially reduced in diameter by the press-fitting of the conductive member 16 to the outer periphery of the wedge 14. Thereby, the wedge 14 is firmly fixed to the outer periphery of the cable conductor 1. The anchoring unit 15 includes an anchoring body 17, a pushing member 18 movably disposed in an axial direction of the anchoring body 17 at a position below the anchoring body 17, and a pushing member 18.
Projecting member 19 that projects radially by the axial movement of
And an elastic member 20 disposed between the retaining body 17 and the pressing member 18. The retaining body 17 includes a cylindrical portion 17a and an annular locking member 17b inwardly connected to the upper end of the cylindrical portion 17a. The portion is locked in the locking groove 14c of the wedge 14 with a predetermined movable width L (for example, about 4 mm) so as to be movable in the axial direction of the wedge 14.
In the central portion of the cylindrical portion 17a and a portion slightly below the central portion,
A through hole 17c and a pin insertion hole (not shown) are formed respectively. The through hole 17c is provided with a tapered portion whose diameter is reduced from the inner peripheral side to the outer peripheral side of the cylindrical portion 17a, and the diameter of the outer peripheral side is substantially equal to or larger than the diameter of a ball as a projecting member 19 described later. It is slightly smaller. The number of the through holes 17c and the number of the pin insertion holes may be one or more. However, from the viewpoint of balance, the through holes 17c and the pin insertion holes are preferably provided evenly along the circumferential direction at four places of the cylindrical portion 17a. In this case, it is preferable to arrange the through hole 17c and the pin insertion hole such that the pin insertion hole is located between the through holes 17c, that is, the two are alternately arranged. A C-shaped spring pin described later is mounted in the pin insertion hole. The protruding member 19 is formed of a ball (for example, a steel ball having a diameter of 6 mm). The ball serving as the protruding member 19 is disposed in the through hole 17c so that a half of the protruding member 19 can protrude from the outer peripheral surface of the cylindrical portion 17a. You. The pushing member 18 has a middle diameter cylindrical portion 18a slightly smaller in diameter than the inner diameter of the cylindrical portion 17a of the retaining body 17, and a small diameter connected to the upper end of the middle diameter cylindrical portion 18a via a tapered inclined portion 18b. A cylindrical portion 18c;
An annular spring locking member 18d protruding inward from the inner periphery of the upper end of the middle diameter cylindrical portion 17a, and a press ring 18e made of an annular hard plastic resin or the like fitted to the lower end of the middle diameter cylindrical portion 18a. And the medium-diameter cylindrical portion 18a
A slit 18f having a predetermined length is formed in the center of the shaft along the axial direction. The slit 18f is provided at a position corresponding to the above-described pin insertion hole. Elastic member 20
Is constituted by a coil-shaped spring, and the spring as the elastic member 20 has a locking member 17 at its upper end side.
b, is fitted into an annular concave groove 17d formed on the lower surface side,
The lower end is disposed so as to contact the upper surface of the spring locking member 18d. Here, the outer diameter of the spring as the elastic member 20 is smaller than that of the small-diameter cylindrical portion 1 forming the pressing member 18.
The inner diameter of the spring is slightly smaller than the inner diameter of the spring locking member 18d constituting the pressing member 18. Next, an assembling procedure of the wedge 14, the conductive member 16, and the anchoring unit 15 having such a configuration (hereinafter, these members are referred to as “conductor restraining units”) will be described. First, the spring pin 21 is driven into the pin insertion hole of the cylindrical portion 17a of the anchoring body 17 constituting the anchoring unit 15 so that the tip does not protrude from the inner peripheral surface side of the cylindrical portion 17a, and the spring pin 21 also An adhesive tape made of a cellophane tape is wound, and a ball as a protruding member 19 previously disposed in the through hole 17c is adhered to the adhesive tape to temporarily fix the ball. Next, the upper end side of the coil-shaped spring as the elastic member 20 is fitted into the concave groove 17d of the locking member 17b of the anchoring body 17, and the lower end side is pressed by the spring locking member 18d of the pressing member 18 to press the pressing ring of the pressing member 18. The upper end surface of the cylindrical body 17
a until it comes into contact with the lower end surface of the sheet a, and temporarily fixed with an adhesive tape made of cellophane tape so as to maintain this state. Thereby, the spring as the elastic member 20 is compressed, and a predetermined elasticity is given to this. Subsequently, the spring pin 21 inserted in advance is fixed such that its head (not shown) does not protrude from the outer peripheral surface of the cylindrical portion 17a of the retaining body 17, ie, the outer peripheral surface of the cylindrical portion 17a of the retaining body 17 The spring pin 21 is driven so as to be flush with the head, and the tip of the spring pin 21 is
Into the slit 18f. Then, the pressing member 18
Can move up and down within a range in which the tip of the spring pin 21 moves freely within the slit 18f, that is, within a range in the longitudinal direction of the slit 18f. This prevents the pushing member 18 from being detached from the retaining body 17. Then, after removing each adhesive tape (cellophane tape) and confirming the operation of each component in the anchoring unit 15, the locking member 1 of the anchoring body 17 is removed.
7b is pushed into the locking groove 14c of the wedge 14 and fitted. Next, the wedge 14 assembled as described above is used.
As shown in FIG. 1, the anchoring unit 15 is inserted around the outer periphery of the upper end of the cable conductor 1, and then the conductive member 16 is inserted into the outer periphery of the wedge 14 from the upper end of the cable conductor 1, so that the anchoring unit 15 side Press-fit. As a result, the wedge 14 is firmly fixed to the cable conductor 1, and the conductive member 16 electrically connects the cable conductor 1 to the internal conductor forming the bushing via the conductor connector 16c. In the above embodiment, a description is given of a case where a conductive member formed of a cylindrical metal plug having a tapered portion formed at the same inclination as the tapered portion of the wedge on the inner peripheral surface is press-fitted on the outer periphery of the upper half portion of the wedge. However, the present invention is not limited to this. For example, a press-fit metal cylinder having a tapered portion formed on the outer periphery of the upper half portion of the wedge with the same inclination as the tapered portion of the wedge on the inner peripheral surface is press-fitted. A conductive member made of a cylindrical metal plug is fitted around the outer periphery of the tightened metal cylinder, and the conductive member electrically connects between the tightened metal cylindrical body and the internal conductor forming the bushing. You may do it. Alternatively, a metal sleeve that does not expand and contract in the radial direction may be used as the wedge, and this may be directly compression-connected to the outer periphery of the cable conductor. Next, a method of attaching the cable terminal processing unit assembled as described above to the bushing will be described. First, the bushing 22 is a cylindrical bushing main body 2 made of a molded body made of epoxy resin or the like having a receiving end 23a for a cable terminal processing portion at a lower end portion.
3 and a cylindrical inner conductor 24 closed at the upper end and embedded in the inner periphery of the upper end of the bushing main body 23. The inner conductor 24 is connected to an upper cylindrical portion 24a having a closed upper end and a lower end of the upper cylindrical portion 24a.
A middle cylindrical portion 24b having a slightly larger diameter and a storage recess 24d formed of an annular groove or the like on the inner peripheral surface thereof; and a middle portion 24b provided at the lower end of the middle cylindrical portion 24b to have a slightly larger diameter than the middle cylindrical portion 24b. And a lower cylindrical portion 24c. In addition,
The storage recess 24d has a tapered portion that decreases in diameter in the radial direction from the inner peripheral surface of the middle cylindrical portion 24b, and the diameter of the storage recess 24d is substantially equal to the diameter of the ball as the protruding member 19. And the bushing 2 of such a configuration
Numeral 2 is hermetically mounted via a gasket 25b or the like to an opening 25a provided at the bottom of a sealed case 25 of an electric device (not shown) that houses a switch and a transformer. As shown in FIG. 1, the cable terminal processing section is inserted into the bushing 22 having such a configuration, and the conductor connector 16 c (see FIG. 2) of the conductive member 16 is inserted into the upper cylindrical section 24 a of the inner conductor 24. Make electrical contact with the peripheral surface. In this case, it is preferable to form a gap of about 5 mm between the upper end surface of the cable conductor 1 and the lower end surface of the closed portion 24e of the inner conductor 24. Here, since the conductor connector 16c has the property of expanding and contracting in the radial direction, the conductive member 16 is connected to the conductor connector 16c.
It is possible to slide in the axial direction within the inner peripheral surface of the upper cylindrical portion 24a via the. Next, a spindle-shaped pre-molded insulator composed of an insulating portion 9a made of a rubber-like elastic material and a semi-conductive portion 9b made of a semi-conductive rubber-like elastic material, which has been inserted into the outer periphery of the cable insulating layer 8 in advance. 9 is pressed toward the upper end by a predetermined distance (for example, about 4 mm) by an annular pressing fitting 26 constituting the compression device, and the retention unit 1 is pressed.
5 is pushed up. Then, the ball as the protruding member 19 is pushed up radially outward from the small-diameter cylindrical portion 18c constituting the pushing member 18 along the outer surface of the inclined portion 18b. Further, the pressing member 18 is further connected to the upper cylindrical portion 24a and the middle cylindrical portion 24b in which the upper end of the locking member 17b forms the internal conductor 24.
When the ball is pushed up to a position where it comes into contact with the continuous portion, the half of the ball as the projecting member 19 projects from the through hole 17c of the cylindrical portion 17a.
d. In addition, the projecting member 1
The ball as 9 rides on the outer peripheral surface of the medium-diameter cylindrical portion 18d constituting the pushing member 18, and this state is maintained, so that the protruding member 19 is prevented from dropping inward in the radial direction. As a result, the retention unit 15 is
4 to prevent the cable from being pulled out. In the drawing, reference numeral 27 denotes a cable protection fitting for protecting the cable terminal processing unit, 28 denotes a fastening bolt for airtightly fastening an upper flange 27a of the cable protection fitting and a lower flange 23b of the bushing body 23 via a gasket 29,
30 is a spring constituting the compression device, 31 is a ground wire,
Reference numeral 32 denotes a waterproof protective layer. Next, FIG.
A method for extracting a cable from a bushing will be described based on (a) to (c). First, at the terminal connection portion of the power cable shown in FIG.
Further, the cable protection fitting 27 and the pressing devices 26 and 30 for the pre-molded insulator 9 are removed to expose the cable terminal processing section as shown in FIG. Here, the upper end of the inner peripheral edge of the locking member 17b constituting the retaining unit 15 is in contact with the upper end of the locking groove 14c of the wedge 14, that is, the lower end surface of the annular projection 14a. This is based on the fact that the cable thermally expands and contracts in the axial direction when the conductor 1 is energized, and moves due to its own weight. Next, as shown in FIG. 3 (b), a so-called cable core near the cable end is gripped, and is held at a predetermined length in the axial direction of the cable toward the upper end, that is, the movable groove 14c of the wedge 14 is movable. Push up by a distance corresponding to width L (about 4 mm). In this case, the pre-mold insulator 9 is held as it is in the receiving port 23a of the bushing 22, and only the cable core moves toward the upper end. Subsequently, as shown in FIG. 3 (c), the cable core is gripped, and this is moved downward by a distance corresponding to the movable width L of the wedge 14 in the axial direction of the cable, that is, by a distance moved upward. Pull back. Then, since the pre-molded insulator 9 is formed of a rubber-like elastic material, that is, is in close contact with the outer peripheral surface of the cable insulating layer 8, the above-described movable width remains attached to the outer periphery of the cable core. It will be pulled back downward by a distance corresponding to L. As a result, the pressing member 18 is lowered to the lower portion by the elastic member 20, and the lock of the ball as the projecting member 19 is released. Thereby, in a state where the pre-mold insulator 9 is mounted on the outer periphery of the cable insulating layer 8,
The cable termination can be pulled out of the bushing 22. In the above-described cable pulling method, the lock can be released only by grasping the cable side, pushing up the cable side, and then pulling down the cable by the pushed distance. That is, in the cable pulling method of the present invention, it is possible to release the lock of the cable conductor only by grasping the easily grippable cable and moving it up and down by a distance equivalent to the pull-down distance of the conventional pre-molded insulator. As a result, the pre-mold insulator can be taken out of the bushing without damaging the pre-mold insulator, and the pre-mold insulator can be reused. In the above-described embodiment, the case where the present invention is applied to a terminal connection portion of an electric wire / cable of a power device is described. However, the present invention is not limited to such a case. The present invention may be applied to a so-called straight connection portion or branch connection portion for connecting cables.

As is apparent from the above description, according to the cable connecting portion and the cable pulling method using the same according to the present invention, the cable conductor can be axially moved to the inner conductor via the conductor restraining unit. Because it is locked,
It is possible to reduce the size of the current-carrying part, save labor for assembling the current-carrying parts, and improve the insulation characteristics of the cable connection part. In addition, since the cable conductor can be unlocked only by grasping the cable and moving it up and down a predetermined length, it is possible to remove the pre-mold insulator without requiring a large amount of effort and without damaging it during disassembly. It is possible to reuse the pre-molded insulator.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a cable connecting portion of the present invention.

FIG. 2 is a half-cut assembly drawing of a conductor restraining unit according to the present invention.

FIGS. 3A and 3B are half vertical sectional views of a cable connecting portion showing a state of pulling out a cable in the present invention. FIG. 3A is a half vertical sectional view of the cable connecting portion when power is supplied, and FIG. FIG. 3C is a half vertical sectional view of the cable connecting portion showing the raised state, and FIG. 4C is a half vertical sectional view of the cable connecting portion showing a state where the lock of the cable conductor is released.

FIG. 4 is a longitudinal sectional view of a main part of a conventional power cable terminal connection portion.

FIG. 5 is a vertical cross-sectional view of a main part showing a state in which a lock of a cable conductor in a conventional power cable terminal connection portion is released.

[Explanation of symbols]

 14 ... wedge 15 ... retention unit 16 ... conduction member 17 ... retention body 18 ... pushing member 19 ...・ Protruding member 20 ・ ・ ・ ・ ・ ・ Elastic member

Claims (5)

(57) [Claims] 1. A cylindrical wedge fixed to an outer periphery of an upper end portion of a cable conductor exposed by stepping off a cable terminal, a cylindrical anchoring unit fitted to an outer periphery of the wedge and having a locking means, A conducting member that conducts between the wedge and a cylindrical internal conductor that constitutes a bushing.The outside of the retention unit is locked to the inner peripheral surface of the internal conductor by the locking means, and the inside is A cable connection portion, which is movably locked on an outer peripheral surface of the wedge in an axial direction of the wedge. 2. A made of a metal sleeve the wedge is expanded and contracted in the radial direction, according to claim 1, wherein the conductive member consisting of a cylindrical metal plug in the upper half periphery over the metal sleeve, characterized in that it is pressed Cable connection. 3. A taper portion is formed on an outer peripheral surface of an upper half portion of the wedge and an inner peripheral surface of the conductive member so as to reduce a diameter at a same inclination from a lower end to an upper end. The cable connection part according to claim 1 or 2, wherein 4. A tape-shaped conductor connector electrically connected to an inner peripheral surface of the inner conductor along a circumferential direction in an annular concave groove formed on an outer peripheral surface of the conductive member. The cable connection part according to any one of claims 1 to 3 , wherein a cable is mounted. 5. The cable connecting portion according to claim 1 , wherein the cable near the cable terminal is gripped, the cable is moved to an upper end by a predetermined length, and then pulled back by a predetermined length. A cable pulling method, comprising releasing the lock and then pulling out the cable.