JP2017135944A - Cable connection portion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cable connection portion with excellent safety and reliability which can deal with large-size power cables of 1200 mmor more.SOLUTION: A cable connection portion comprises a bushing and a cable terminal portion. The cable terminal portion has a connection terminal to be fitted to a cable conductor of a power cable. The connection terminal has: a first plug 31; a second outer plug 32; a lock mechanism for fixing the second plug to an inner conductor; a contact maker for conducting the first plug to the second plug; and a locking member for locking the first plug to the second plug. Between the first plug and the second plug is provided a clearance C at which the first plug can be engaged with the second plug, in a tilting state. A groove on which is mounted the locking member 35 has a groove width in which the locking member can be mounted on the groove even if the first plug is engaged with the second plug, in the tilting state. The contact maker is formed of a V-shape multi-ram band.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a cable connecting portion, and more particularly to a connecting material to be attached to a cable terminal portion.

  Conventionally, as cable connection parts, there are termination connection parts such as gas termination connection parts, oil termination connection parts, air termination connection parts, and intermediate connection parts such as straight connection parts and branch connection parts. It is formed by connecting a cable end portion to which a connecting material is attached to a main body material (referred to as “bushing”) having an inner cylinder and an insulating cylinder made of an epoxy resin or the like disposed on the outer periphery of the inner conductor. In the cable connection portion, for example, the connection terminal is compression-connected to the cable conductor, and this connection terminal is electrically connected to the inner conductor of the polymer sleeve through a contact (for example, Patent Documents 1 and 2).

  In Patent Documents 1 and 2, the connection terminal has a double plug structure including a first plug and a second plug disposed outside the first plug, and the first plug serves as a cable conductor. It is compression-connected and fixed to the second plug. In addition, the first plug and the second plug are electrically connected via a contact, and the cable terminal portion to which the first plug and the second plug are attached has a lock mechanism having a protruding body such as a ball. Is fixed to the inner conductor. Such a structure is easier to insert / remove (plug-in / plug-out) than the structure in which the inner conductor and the connection terminal are connected via a contact called a tulip contact, and the cable connection part can be made smaller. You can plan.

Japanese Patent No. 3192097 Japanese Patent No. 3280178

In the cable connection portion, the cable terminal portion is inserted straight into the bushing. Therefore, in the structures described in Patent Documents 1 and 2, the second plug needs to be arranged so as to be on the same axis as the power cable. However, for example, in a 154 kV class power cable, in the case of a large size cable having a nominal cross-sectional area of the cable conductor of 1200 mm ² or more, the cable conductor is bent when the first plug is compression-connected (hereinafter referred to as “compression bending”). And the second plug may be mounted in an inclined state with respect to the axis of the power cable. In this case, the contact pressure between the second plug and the inner conductor becomes uneven in the circumferential direction, and the contact resistance becomes unstable. For example, the reliability and safety of the cable connection portion may be impaired.

An object of the present invention is to provide a cable connecting portion that is excellent in safety and reliability and can handle a large-sized power cable of 1200 mm ² or more.

A cable connection portion reflecting one aspect of the present invention is a cable connection portion including at least an internal conductor and a bushing having an insulating tube disposed on the outer periphery of the internal conductor, and a cable terminal portion attached to the bushing. And
The cable terminal portion has a connection terminal attached to the cable conductor of the power cable,
The connection terminal is
A first engaging portion located at the most distal end portion, a first energizing portion provided continuously with the engaging portion, and a compression connecting portion provided continuously with the first energizing portion and compressed and connected to the cable conductor. 1 plug,
A top part having an opening into which the engaging part is inserted, and a second plug having a second energization part connected to the top part and electrically connected to the first energization part;
A locking mechanism for fixing the second plug to the inner conductor;
A contact that is disposed on an outer peripheral surface of the first energization unit and that conducts the first energization unit and the second energization unit;
A locking member that is mounted in the groove of the engaging portion and locks the first plug with respect to the second plug;
A clearance is provided between the first plug and the second plug so that the first plug can be engaged with the second plug in an inclined state.
The groove has a groove width in which the locking member can be mounted even when the first plug is engaged with the second plug in an inclined state.
The contact is formed of a V-shaped multilam band.

ADVANTAGE OF THE INVENTION According to this invention, it is excellent in reliability and safety | security, and the cable connection part which can respond to a large size power cable of 1200 mm < ² > or more is provided.

It is sectional drawing which shows the cable connection part which concerns on embodiment of this invention. It is a figure which shows the connection structure of a cable terminal part and an internal conductor. It is a figure which shows the structure of a connection terminal. It is a figure which shows the engagement state of a 1st plug and a 2nd plug.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a cable connecting portion according to an embodiment of the present invention. The cable connection portion 1 in FIG. 1 is an example of an air termination connection portion. Here, as an example, a direct-mold type polymer sheath is formed by directly molding a polymer covering made of silicone rubber or the like on the outer peripheral surface of an insulating cylinder. The cable termination connection using a tube is shown. As shown in FIG. 1, the cable connecting portion 1 is configured by attaching the cable terminal portion 20 to the polymer sleeve 10.

  In the cable connection portion 1, the polymer sleeve 10 is integrally formed with the inner conductor 11, the insulating cylinder 12 provided on the outer periphery of the inner conductor 11, the polymer covering 13 provided on the outer periphery of the insulating cylinder 12, and the insulating cylinder 12. The shielding metal fitting 14 and the lower metal fitting 15 are provided. In the cable connection portion 1, the polymer sleeve 10 is a bushing. The inner conductor 11, the insulating cylinder 12, the polymer cover 13 and the shielding metal fitting 14 are integrally formed by molding. The polymer cannula 10 is a straight polymer cannula to which the cable end portion 20 is connected from the axial direction.

  The inner conductor 11 is formed of a conductive material suitable for energization made of, for example, copper, aluminum, a copper alloy, or an aluminum alloy. The inner conductor 11 has a conductor insertion portion (reference numeral omitted) for electrically connecting the cable conductor 51 at the rear end.

  The insulating cylinder 12 is formed of a hard plastic resin material (for example, epoxy resin or FRP (Fiber Reinforced Plastics)) having high mechanical strength. The insulating cylinder 12 has a cone-shaped receiving port (reference numeral omitted) for receiving the cable terminal portion 20 at the rear end. This receiving port communicates with the conductor insertion portion of the inner conductor 11.

  The polymer covering 13 is formed of a material excellent in electrical insulation performance (for example, a polymer material such as silicone polymer). The polymer covering 13 has an umbrella-shaped collar part (reference numeral omitted) arranged on the outer peripheral surface so as to be spaced apart in the longitudinal direction.

  The shielding metal fitting 14 is a shielding layer of the polymer sleeve 10 formed integrally with the insulating cylinder 12. The shielding metal fitting 14 has an electric field relaxation function and relaxes the electric field of the polymer sleeve 10. Since the shielding fitting 14 is embedded in the insulating cylinder 12 and the insulating cylinder 12 and the shielding fitting 14 are integrated, the polymer sleeve 10 can be mechanically reinforced, and the lower fitting 15, the bottom fitting 16, and The polymer cannula 10 can be easily and stably attached to the mount 62 via the support insulator 61.

  The lower metal fitting 15 has a cylindrical shape and is arranged on the outer periphery of the rear end portion of the insulating cylinder 12 (the rear end side with respect to the shielding metal fitting 14). The lower metal fitting 15 is fixed to the shielding metal fitting 14 by bolting the flange (reference numeral omission) at the front end of the lower metal fitting 15 to the flange portion (reference numeral omission) of the rear end portion of the shielding metal fitting 14. A support insulator 61 is disposed on the rear end side of the upper flange and is fixed by bolting.

  In the cable connection portion 1, the cable terminal portion 20 is configured by attaching connection materials such as the connection terminal 21, the stress cone 22, the compression device 23, and the protective metal fitting 24 to the distal end portion of the power cable 50.

The power cable 50 is a 154 kV class power cable insulated with rubber or plastic. Here, the nominal cross-sectional area of the cable conductor is 2000 mm ² . The power cable 50 includes, in order from the center, a cable conductor 51, a cable insulator 52, a cable outer semiconductive layer 53, a cable shielding layer 54, a cable sheath 55, and the like. In the cable terminal portion 20, each layer is exposed by stripping a predetermined length from the tip of the power cable 50.

  A conductive connection terminal 21 suitable for energization made of, for example, copper, aluminum, a copper alloy, or an aluminum alloy is connected to the cable conductor 51 by compression. A stress cone 22 is attached to the outer periphery extending from the cable insulator 52 to the tip of the cable outer semiconductive layer 53. A compression device 23 and a protective metal fitting 24 are attached to the rear end side of the stress cone 22. The protective metal fitting 24 has a cylindrical shape with a smaller diameter than the lower metal fitting 15. The structure of the connection terminal 21 will be described later.

  The stress cone 22 has an insulating portion 221 on the front end side made of an insulating rubber material (for example, ethylene propylene rubber (EP rubber) or silicone rubber) and a semiconductive portion 222 on the rear end side, and the spindle as a whole. It is formed into a shape. In the present embodiment, the semiconductive portion 222 is formed of a semiconductive rubber material (for example, semiconductive ethylene propylene rubber (EP rubber) or silicone rubber), and the insulating portion 221 and the semiconductive portion 222 are molded. It is integrally formed by molding.

  The rear end portion of the semiconductive portion 222 is connected to the cable external semiconductive layer 53 of the power cable 50. The insulating part 221 has a shape corresponding to the receiving port of the insulating tube 12 of the polymer sleeve 10 and is pressed against the receiving port of the insulating tube 12 by the compression device 23.

  The compression device 23 includes a pressing metal 231, a spring 232, and a pressing metal flange 233. The press fitting 231 has an opening having a shape (trumpet shape) corresponding to the outer peripheral surface of the rear end portion of the stress cone 22 (the outer peripheral surface of the semiconductive portion 222) at the front end portion. A coiled spring 232 is disposed at the rear end of the pressing metal 231 and is supported by the pressing metal flange 233. The metal fitting flange 233 is fixed to the lower metal fitting 15 by bolting the metal fitting flange 233 to the rear end of the lower metal fitting 15 (not shown). In addition, the cable shielding layer 54 of the power cable 50 is electrically connected to the metal fitting flange 233.

  The cable terminal portion 20 is assembled by stripping the tip of the power cable 50, attaching the protective fitting 24, the compression device 23, and the stress cone 22 to the power cable 50 and attaching the connection terminal 21 to the cable conductor 51.

  Then, the front end portion of the assembled cable terminal portion 20 is inserted into the receiving port of the insulating cylinder 12, and the pressing metal flange 233 is bolted to the rear end surface of the lower metal fitting 15 while compressing the spring 232 of the compression device 23 (not fixed). The cable terminal portion 20 is attached to the polymer sleeve 10 by bolting the protective metal fitting 24 to the lower metal fitting 15. The distal end portion of the stress cone 22 is pressed against the inner wall surface of the receiving port of the insulating cylinder 12, and the connection terminal 21 is electrically connected to the conductor insertion portion of the inner conductor 11. In addition, an anticorrosion layer (not shown) for waterproofing is disposed at the rear end of the protective metal fitting 24. The cable connecting portion 1 can be assembled by a relatively simple operation by slip-on connection.

  FIG. 2 is a diagram illustrating a connection structure between the cable terminal portion 20 and the internal conductor 11. FIG. 3 is a diagram illustrating the structure of the connection terminal 21.

  As shown in FIGS. 2 and 3, the connection terminal 21 has a double plug structure including a first plug 31 and a second plug 32 arranged outside the first plug 31. The second plug 32 is fixed to the inner conductor 11 by the lock mechanism 36.

  The first plug 31 is compressed to the cable conductor 51 by being connected to the engaging portion 311 located at the most distal end side, the first energizing portion 312 provided continuously with the engaging portion 311, and the first energizing portion 312. It has the compression connection part 313 connected. The engaging portion 311 and the first energizing portion 312 have a two-stage columnar shape, and the compression connecting portion 313 has a cylindrical shape with the distal end side closed. The first plug 31 has a constricted portion 314 between the first energizing portion 312 and the compression connecting portion 313. Thereby, the deformation of the compression connecting portion 313 due to the compression does not reach the first energization portion 312.

  The second plug 32 includes a top portion 321, a second current-carrying portion 322 that is connected to the top portion 321, and is electrically connected to the first current-carrying portion 312 through a second contactor 34 that will be described later. A fixing portion 323 that is connected to the portion 322 and is fixed to the inner conductor 11 is provided. The second plug 32 has a cylindrical shape as a whole. In the cable connection portion 1, since the cable terminal portion 20 is inserted straight into the polymer sleeve 10, the second plug 32 is disposed on the same axis as the power cable 50.

  The cable conductor 51 is inserted into the hollow portion (conductor connection hole) 313a of the compression connection portion 313 and is compression-connected. An engagement portion 311 is inserted into the opening 321a formed in the top portion 321 so that the tip portion slightly protrudes, and the first plug 31 is not detached from the second plug 32. 35 is mounted.

  A first contactor 33 (not shown in FIG. 3) is disposed in a groove 312a formed on the outer peripheral surface of the first energization unit 312. The first contactor 33 is a V-shaped multilam band. For example, “La-CUT / 0.25 / 0 (product number)” manufactured by Multi-Contact Co., Ltd., which is known as a multi-face contact type contactor, can be applied as the first contactor 33. The first plug 31 and the second plug 32 are electrically connected via the first contactor 33.

  A second contactor 34 (not shown in FIG. 3) is disposed in the groove 322a formed on the outer peripheral surface of the second energization section 322. The second contact 34 is “La-Cus / 0.15 (product number)” manufactured by Multi-Contact. The second plug 32 and the internal conductor 11 are electrically connected via the second contact 34.

  The lock mechanism 36 includes a fixture 361, a ball 362, a stopper 363, and a coil spring 364. The fixing portion 323 of the second plug 32 has a ball accommodation hole 323 a that accommodates the ball 362. The ball housing hole 323a is a tapered hole that decreases in diameter from the inside toward the outside. The ball accommodation holes 323a are provided at four locations at regular intervals along the circumferential direction, for example. The inner conductor 11 has a positioning hole 11a on the inner peripheral surface at a position corresponding to the ball housing hole 323a when the cable end portion 50 is attached to the polymer sleeve 10.

  The fixing bracket 361 is movable in the axial direction in a state where the coil spring 364 is disposed between the step 323b of the fixing portion 323 and the fixing bracket 361 and the ball 362 is disposed in the ball receiving hole 323a of the fixing portion 323. Be placed. Before the second plug 32 is fixed to the internal conductor 11, the ball 362 is accommodated in the ball accommodating groove 361a of the fixture 361 (the accommodated state is not shown). A stopper 363 is disposed on the rear end side of the fixing bracket 361.

  When the stopper 363 is urged toward the distal end side by the stress cone 22, the fixing bracket 361 moves to the distal end side accordingly. As the fixing bracket 361 moves against the urging force of the spring 364, the ball 362 is pushed outward (to the inner conductor 11 side) by the support portion 361b of the fixing bracket 361, and gradually from the ball receiving hole 323a. Is exposed. When the fixture 361 moves to the specified position, the ball 362 engages with the positioning hole 11a of the inner conductor 11. Thereby, the cable terminal part 50 is fixed to the polymer cannula 10 so as not to fall off.

  When the cable terminal portion 20 is pulled out, the stress cone 22 is retracted and the locking by the stopper 363 is released. Since the fixture 361 is retracted to the lower end side by the biasing force of the coil spring 364, the ball 362 moves inward and returns to its original state. Thereby, the fixed state of the inner conductor 11 and the second plug 32 is released, and the cable terminal portion 20 can be easily pulled out from the polymer sleeve 10.

  In the cable connection portion 1, the connection terminal 21 having a double plug structure is interposed between the cable conductor 51 and the inner conductor 11, and the second plug 32 is fixed to the inner conductor 11 by the lock mechanism 36. Thus, the size of the conductor connecting portion including 21 can be significantly reduced, and the overall size of the cable connecting portion can be reduced. Further, the cable connecting portion 1 can be easily assembled and disassembled without using a special tool or the like.

Furthermore, in the cable connection part 1 of this Embodiment, the connection terminal 21 has the structure shown below so that it can respond | correspond as a connection part (here termination | terminus connection part) of a large sized electric power cable of 1200 mm < ² > or more.

  FIG. 4 is a diagram showing an engaged state of the first plug 31 and the second plug 32. FIG. 4A shows a case where no compression bending occurs, and FIG. 4B shows a case where compression bending occurs.

  As shown in FIG. 4, clearances C (C1 to C3) are provided between the first plug 31 and the second plug 32. The first plug 31 is loosely fitted to the second plug 32. The first clearance C1 is set within a corresponding range of the first contactor 33 (for example, 0.2 to 1.2 mm). The second clearance C2 and the third clearance C3 are set to such an extent that the inclination of the first plug 31 due to compression bending can be absorbed (for example, 0.2 to 1.0 mm).

  Further, the width W of the groove 311a of the engaging portion 311 of the first plug 31 is larger than the width of the C-type retaining ring 35, and the first plug 31 is inserted into the second plug 32 in an inclined state. Even in this case, the second plug 32 is set to be exposed upward. The width W of the groove 311 a is set based on the allowable inclination angle of the second plug 32.

  As shown in FIG. 4A, when no compression bending occurs, the axis of the first plug 31 coincides with the axis of the power cable 50. When the second plug 32 is attached to the first plug 31, the axis of the second plug 32 also coincides with the axis of the power cable 50.

  On the other hand, as shown in FIG. 4B, when compression bending occurs, the axis of the first plug 31 is inclined with respect to the axis of the power cable 50. Since the clearance C is provided between the first plug 31 and the second plug 32, the second plug 32 is inclined with respect to the inclined first plug 31 so as to be on the same axis as the power cable 50. A plug 32 can be attached. At this time, a part of the groove 311a of the engaging portion 311 of the first plug 31 (for example, the groove on the right side in FIG. 4B) sinks more than the upper surface of the second plug 32, but the groove 311a remains in the first plug 31. Therefore, the C-type retaining ring 35 is not prevented from being mounted. Accordingly, the first plug 31 is inclined inside the second plug 32, but the second plug 32 can be attached so as to be on the same axis as the power cable 50.

  As described above, the cable connecting portion 1 includes the inner conductor 11 and the polymer sleeve 10 (bushing) having the insulating cylinder 12 disposed on the outer periphery of the inner conductor 11, and the cable terminal portion 20 attached to the polymer sleeve 10. . The cable terminal portion 20 includes a connection terminal 21 that is attached to the cable conductor 51 of the power cable 50. The connection terminal 21 is compression-connected to the cable conductor 51 connected to the engaging portion 311 located at the most distal end, the first energizing portion 312 connected to the engaging portion 311, and the first energizing portion 312. A first plug 31 having a compression connecting portion 313, a top portion 321 having an opening 321a into which the engaging portion 311 is inserted, and a second portion that is connected to the top portion 321 and is electrically connected to the first energization portion 312. A second plug 32 having a current-carrying part 322, a lock mechanism 36 for fixing the second plug 32 to the inner conductor 11, and an outer peripheral surface of the first current-carrying part 312 are disposed on the first current-carrying part 312. And a first contactor 33 that conducts between the second energization part 322 and a C-type retaining ring that is mounted in the groove 311a of the engagement part 311 and that locks the first plug 31 with respect to the second plug 32. 35 (locking member). A clearance C is provided between the first plug 31 and the second plug 32 so that the first plug 31 can be engaged with the second plug 32 in an inclined state. The groove 311a has a groove width W in which the C-type retaining ring 35 can be mounted even when the first plug 31 is engaged with the second plug 32 in an inclined state. The first contactor 33 is formed of a V-shaped multilam band.

The cable connecting portion 1 has excellent reliability and safety, and can also cope with a large-sized power cable of 1200 mm ² or more. That is, even if a compression bend occurs when the first plug 31 is compression-connected to the cable conductor 51, the second plug 32 can be attached so as to be in the same axis as the power cable 50. Therefore, when the cable terminal portion 20 is attached to the polymer sleeve 10, the contact pressure between the second plug 32 and the inner conductor 11 becomes uniform in the circumferential direction, and the contact resistance is stabilized. , Can ensure safety. Further, even if the clearance C1 between the first energization part 312 and the second energization part 322 becomes nonuniform in the circumferential direction due to the compression bending, the first contactor made of a V-shaped multi-ram band. 33 ensures a good conduction state.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the above embodiment, and can be changed without departing from the gist thereof.

  For example, in the embodiment, instead of the lock mechanism 36 using the ball 362, a lock mechanism using an appropriately shaped pin or the like may be applied. Further, instead of the C-type retaining ring 35, an appropriate locking member may be applied.

  The present invention is not only an air terminal connection part by the polymer sleeve of the embodiment, but if it is a so-called prefabricated cable connection part, the air terminal connection part, the gas terminal connection part, the oil terminal connection part, In addition, it can be widely applied to intermediate connection parts such as straight connection parts and branch connection parts. In addition, in the present invention, the bushing includes, in addition to the polymer sleeve as in the embodiment, main body materials such as a gas end connection portion and an oil end connection portion, and a main body material of an intermediate connection portion. In the present invention, the bushing has at least an inner conductor and an insulating cylinder (for example, a hard plastic resin material having high mechanical strength such as epoxy resin and FRP) disposed on the outer periphery of the inner conductor.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 Cable connection 10 Polymer sleeve (bushing)
DESCRIPTION OF SYMBOLS 11 Inner conductor 20 Cable terminal part 21 Connection terminal 31 1st plug 32 2nd plug 33 1st contactor 34 2nd contactor 35 C-type retaining ring (locking member)
36 Lock mechanism 50 Power cable 51 Cable conductor 311 Engagement part 311a Groove 312 First energization part 313 Compression connection part 321 Top part 321a Opening 322 Second energization part 323 Fixing part C, C1 to C3 Clearance

Claims (3)

A cable connecting portion comprising at least a bushing having an inner conductor and an insulating cylinder disposed on the outer periphery of the inner conductor, and a cable terminal portion attached to the bushing,
The cable terminal portion has a connection terminal attached to the cable conductor of the power cable,
The connection terminal is
A first engaging portion located at the most distal end portion, a first energizing portion provided continuously with the engaging portion, and a compression connecting portion provided continuously with the first energizing portion and compressed and connected to the cable conductor. 1 plug,
A top part having an opening into which the engaging part is inserted, and a second plug having a second energization part connected to the top part and electrically connected to the first energization part;
A locking mechanism for fixing the second plug to the inner conductor;
A contact that is disposed on an outer peripheral surface of the first energization unit and that conducts the first energization unit and the second energization unit;
A locking member that is mounted in the groove of the engaging portion and locks the first plug with respect to the second plug;
A clearance is provided between the first plug and the second plug so that the first plug can be engaged with the second plug in an inclined state.
The groove has a groove width in which the locking member can be mounted even when the first plug is engaged with the second plug in an inclined state.
The cable connection part, wherein the contact is formed of a V-shaped multi-ram band.   The cable connecting portion according to claim 1, wherein a first clearance between the first energizing portion and the second energizing portion is within a corresponding range of the contact.   The cable connecting portion according to claim 2, wherein a second clearance between the engaging portion and the top portion is smaller than the first clearance.

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