JP6611654B2 - Cable connecting device and cable connecting portion - Google Patents

Description

  The present invention relates to a cable connecting device for connecting a cable conductor to a prefabricated cable connecting portion by a plug-in structure, and a cable connecting portion using the cable connecting device.

  In general, in a terminal connection portion of a power cable, a cable connection device (also referred to as a connection terminal) is attached to a tip portion of a cable conductor, and an internal conductor (conductor lead bar) and a cable are connected via the cable connection device. Conductors are electrically connected. In addition, there is also a terminal connection portion in which a spring-like contact (multi-ram band) is disposed on the outer peripheral surface of the cable connection device and the cable conductor and the internal conductor are connected by a plug-in structure (for example, Patent Document 1). ).

  FIG. 1 is a partial cross-sectional view showing a configuration example of a terminal connection portion (in FIG. 1, an air terminal connection portion) 1 that connects a cable conductor and an internal conductor by a plug-in structure. FIG. 2 is an enlarged view showing a plug connection structure to the termination connection portion 1.

  As shown in FIG. 1, the terminal connection portion 1 includes a cable end portion 1A and a polymer sleeve 1B to which the cable end portion 1A is attached. In the following, in the figure, the upper side is referred to as the front end side, and the lower side is referred to as the rear end side.

  The polymer sleeve 1B includes a rod-shaped inner conductor 13 (conductor lead bar) disposed at the center, an insulating cylinder 14 provided on the outer periphery of the inner conductor 13, a polymer covering 15 provided on the outer periphery of the insulating cylinder 14, and an insulating cylinder 14 A shielding metal fitting 16, a lower metal fitting 17, a bottom metal fitting 19, and the like. The inner conductor 13, the insulating cylinder 14, the polymer cover 15, and the shielding metal fitting 16 are integrally formed by, for example, molding.

  The inner conductor 13 is made of a conductive material suitable for energization made of, for example, copper, aluminum, a copper alloy, or an aluminum alloy. The tip 131 of the internal conductor 13 is connected to an overhead wire, a lead-in wire (not shown), or the like. The inner conductor 13 has a straight portion 133 and an enlarged diameter portion 132 having a larger outer diameter than the straight portion 133 formed continuously with the rear end of the straight portion 133. The enlarged diameter portion 132 is a cable conductor. It is electrically connected to a plug 121 compressed and connected to 111.

  The insulating cylinder 14 is made of a hard plastic resin material (for example, epoxy resin or FRP (Fiber Reinforced Plastics)) having high mechanical strength. The cable terminal portion 1 </ b> A is attached to the receiving port of the rear end portion 141 of the insulating cylinder 14.

  The polymer covering 15 is made of a material having excellent electrical insulation performance (for example, a polymer material such as a silicone polymer). A plurality of umbrella-shaped ridges are formed on the outer peripheral surface of the polymer cover 15 so as to be separated in the longitudinal direction.

  The shielding metal fitting 16 has a cylindrical portion embedded concentrically with the internal conductor 13 and a flange portion extending radially outward from the rear end of the cylindrical portion. The cylindrical portion has an electric field relaxation function and relaxes the electric field of the polymer sleeve 1B.

  The lower metal member 17 has a cylindrical shape having a flange portion (hereinafter referred to as “front end flange portion”) at the front end portion, and is disposed on the outer periphery of the rear end portion 141 of the insulating cylinder 14. The lower fitting 17 is fixed to the shielding fitting 16 by bolting the front end flange portion of the lower fitting 17 to the rear end surface of the flange portion of the shielding fitting 16 (not shown).

  The bottom metal fitting 19 is provided on the outer periphery of the front end flange portion of the lower metal fitting 17 and is bolted (not shown) to the rear end surface of the outer peripheral edge portion of the flange portion of the shielding metal fitting 16. The polymer sleeve 1B is fixed to the gantry R via the support lever 18 by fixing the support lever 18 to the rear end surface of the bottom metal fitting 19 with bolts.

  The cable terminal portion 1 </ b> A includes a cable 11 and a connection component 12 attached to the distal end portion of the cable 11. The connection component 12 includes a plug 121, a stress cone 122, a compression device (not shown), a protective metal fitting 123, an anticorrosion layer 124, and the like.

  The cable 11 is a power cable (for example, a CV cable) insulated with rubber or plastic. The cable 11 includes, in order from the inside, a cable conductor 111, an internal semiconductive layer (not shown), a cable insulator 112, an external semiconductive layer (not shown), a cable shielding layer (not shown), a cable sheath 113, and the like. . In the cable terminal portion 1 </ b> A, each layer is exposed by stripping a predetermined length from the tip of the cable 11.

  A conductive plug 121 is connected to the cable conductor 111 by compression. A stress cone 122 in which an insulating rubber layer and a bell mouth shaped semiconductive rubber layer are integrally formed is attached to the outer periphery extending from the cable insulator 112 to the distal end side of the cable external semiconductive layer (not shown). A compression device (not shown) for pressing the stress cone 122 is disposed on the rear end side of the stress cone 122, and a protective metal fitting 123 is attached to the rear end side of the compression device. An anticorrosion layer 124 for waterproofing is formed on the part.

  Here, as shown in FIG. 2, the plug 121 is attached to the terminal connection portion 1 by forming a plug insertion hole 132 a having a shape along the outer shape of the plug 121 in the enlarged diameter portion 132 of the inner conductor 13. This is done by inserting the plug 121 into the plug insertion hole 132a. A cable conductor 111 is compression-connected to the plug 121. Further, a multi-ram band 121 a is fitted on the outer periphery of the plug 121, so that when the plug 121 is inserted into the insertion hole 132 a of the enlarged diameter portion 132 of the inner conductor 13, the cable conductor 111 and the inner conductor 13 are inserted. Are electrically connected via a plug 121 and a multi-ram band 121a. For convenience of explanation, the polymer covering 15 is omitted in FIG. 2 and FIGS. 3 to 5 described later, and the configuration of the main insulating portion and the conductor connecting portion will be mainly described.

JP-A-10-126946

  By the way, when the aluminum conductor is used as the cable conductor 111, it is necessary to make the axial compression length in the plug 121 longer than when the copper conductor is used. This is because the contact resistance of aluminum is larger than that of copper, and therefore, when an aluminum conductor is used, the contact area in the plug needs to be larger than when copper is used. Here, the “aluminum conductor” includes not only a case of being made of pure aluminum but also a case of being made of an aluminum alloy containing aluminum as a main component.

  Thus, in order to increase the axial compression length, it is necessary to increase the length of the plug. Then, since the relative position of the internal conductor 13 and the plug changes, if the position on the ground potential side of the shielding metal fitting 16 or the like does not change, the generated electric field also changes as the relative position changes. Conventionally, in order to cope with this, there has been a problem that the design of the shape of the inner conductor 13 has to be changed.

  This will be described with reference to FIG. The dotted line in the figure indicates the tip position of the plug and the shoulder position connecting the straight portion 133 of the inner conductor 13 to the enlarged diameter portion 132 when a copper conductor is used. As can be seen by comparison with FIG. 2, the aluminum conductor plug 221 is longer in the axial direction than the copper conductor plug 121 (FIG. 2). Therefore, the plug insertion hole 232a into which the aluminum conductor plug 221 is inserted is deeply dug in the distal direction. When the plug 221 is inserted into the plug insertion hole 232a, the distance between the distal end side peripheral edge portion of the plug 221 and the shoulder portion of the internal conductor 13 indicated by the dotted line in the drawing becomes small, as indicated by the symbol L1 in the drawing. In this location, the thickness of the inner conductor 13 is reduced. Here, since the plug 221 is configured to energize the internal conductor 13 via the multi-ram band 221a provided on the side surface portion, the current density at that position when the internal conductor 13 at the position of the symbol L1 becomes thin. Is extremely undesirably large, and abnormal heat generation may occur in the portion. Therefore, the plug insertion into which the plug 221 is inserted by making a design change (design change to increase the axial length of the enlarged diameter part 132) that extends the enlarged diameter part 132 of the inner conductor 13 in the distal direction. Measures are taken to prevent the distance between the peripheral edge on the front end side of the hole 232a and the shoulder of the internal conductor 13 from becoming narrow and the energized portion of the internal conductor from becoming thin.

  However, it is complicated to greatly change the design of the shape of the inner conductor 13 in accordance with the change in the compression length of the plug 221, and when the shape of the inner conductor 13 is further changed, the shape of the other parts does not change. Since the electric field generated is also changed, there is a possibility that the shape of the main insulating portion (shielding metal fitting 16 or insulating cylinder 14) must be changed. In this case, since the termination connecting portion 1 in FIG. 1 is an aerial terminating connection portion, the mold for producing the insulating tube 14 and the mold for producing the polymer covering 15 have to be changed, which is complicated and costly. But it is not preferable. For example, if the shape of the internal conductor 13 is changed so that the enlarged diameter portion 232 of the internal conductor extends in the distal direction, the insulation design of the main insulation portion changes, and specifically, the shielding metal fitting 16 that is at the ground potential. Since the distance between the inner conductor 13 and the inner conductor 13 is shortened, the electric field is concentrated on the portion, and there is a possibility that required electrical characteristics cannot be obtained as the cable terminal connection portion. As a result, there is a possibility that the shape of the shielding metal fitting 16 and the insulating cylinder 14 must be changed.

  2 and 3, the plugs 121 and 221 to be compressed into the cable conductor 111 are described as plugs having a structure in which the plugs 121 and 221 are directly connected to the inner conductor 13 through the multi-ram bands 121a and 221a. A similar problem occurs even in the conventional double plug structure of the inner plug A that is compressed into the plug A and the plug B that is disposed outside the plug A and is connected to the internal conductor 13.

  The present invention has been made in consideration of the above points, and provides a cable connection device and a cable connection portion that can cope with a change in the compression length of a plug without greatly changing the design of an internal conductor.

One aspect of the cable connection device of the present invention is:
A cable connection device attached to the tip of a cable conductor,
An inner plug that is compressed and connected to the cable conductor and has a first current-carrying portion formed by fitting a first contact to the outer periphery of the tip;
A large-diameter portion into which the inner plug is inserted, and a small-diameter portion connected to the large-diameter portion so as to extend from the large-diameter portion in the distal direction. An outer plug having a second energization part fitted;
Equipped,
The inner plug is fixed on the rear end side from the small diameter portion of the outer plug.

One aspect of the cable connecting portion of the present invention is:
A cable connecting portion having the cable connecting device,
An inner conductor disposed in the center, and an insulating cylinder provided on the outer periphery of the inner conductor,
The inner conductor has a straight portion and an enlarged diameter portion having a larger outer diameter than the straight portion connected to the rear end of the straight portion,
The large-diameter portion of the outer plug is disposed in the enlarged-diameter portion, and at least a part of the small-diameter portion of the outer plug is disposed so as to enter the straight portion.

  According to the present invention, since the power is supplied to the internal conductor connected by the small-diameter portion of the outer plug, the cable connection device and the cable connection that can cope with the change in the compression length of the plug without greatly changing the design of the internal conductor. A cable connection using the device can be realized.

Partial sectional view showing a configuration example of a terminal connection portion that connects a cable conductor and an internal conductor by a plug-in structure Sectional view showing the main insulation part of the plug connection structure to the terminal connection part on an enlarged scale Sectional view of the main insulation used to explain the conventional plug connection structure when the plug length is increased Sectional drawing which shows the structure of the main insulation part of the cable connection apparatus which concerns on embodiment, and a termination | terminus connection part Sectional drawing which shows the structure of the main insulation part of the termination | terminus connection part using the cable connection apparatus of embodiment

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

  FIG. 4, in which the same reference numerals are assigned to the parts corresponding to those in FIG. 2, is a cross-sectional view showing the configuration of the main connecting portion of the cable connecting device 300 and the terminal connecting portion 1 according to the embodiment of the present invention. Moreover, FIG. 5 is sectional drawing which shows the structure of the main insulation part of the termination | terminus connection part 1 using the cable connection apparatus 300 of embodiment.

  The cable connection device 300 includes an inner plug 310 (also referred to as “conductor connection terminal”) and an outer plug 320 (also referred to as “adapter”).

  The inner plug 310 has an insertion hole 311 into which the cable conductor 400 is inserted. In the inner plug 310, an aluminum conductor is inserted as the cable conductor 400 into the insertion hole 311. The “aluminum conductor” includes not only a case of being made of pure aluminum but also a case of being made of an aluminum alloy mainly composed of aluminum. In addition, the inner plug 310 has a first contactor 312 formed of, for example, a multi-ram band (also referred to as “multi-contact”) as an energization portion fitted on the outer periphery of the tip end portion. The inner plug 310 has a screw hole 313 at the center of the tip. Further, the inner plug 310 has an annular recess 314 on the outer peripheral surface, and the recess 314 absorbs the extension and deformation of the inner plug 310 when the inner plug 310 is compression-connected to the cable conductor 400. Yes. The recessed portion 314 is provided so as to be connected to each of the energization portion and the compression portion between the energization portion to which the first contact 312 is fitted and the compression portion on the inner plug rear end side.

  The outer plug 320 has a large-diameter portion 321 into which the inner plug 310 is inserted, and a small-diameter portion 322 connected to the large-diameter portion 321 so as to extend from the large-diameter portion 321 in the distal direction.

  The large diameter portion 321 has an insertion hole 323 into which the inner plug 310 is inserted, and the inner plug 310 is inserted into the insertion hole 323. A stopper 324 having a spring member is provided at the outer peripheral position of the rear end of the large diameter portion 321, and the stopper 324 engages with an engagement groove 132 b formed in the enlarged diameter portion 132 of the internal conductor 13. As a result, the movement of the outer plug 320 in the rear end direction is restricted.

  The small-diameter portion 322 has a second contactor 325 formed of, for example, a multi-ram band (also referred to as “multi-contact”) as an energization portion on the outer periphery thereof. The small diameter portion 322 has a through hole 326 in the center.

  In the above configuration, when the terminal connection portion 1 is formed using the cable connection device 300, first, the first contactor 312 is connected to the outer plug 320 in advance by compression connection to the cable conductor 400 and to the outer periphery of the small diameter portion 322. An inner plug 310 with a multi-ram band (here, a multi-ram band) is inserted, and in this state, a male screw structure is formed on the outer periphery of the distal end portion made of, for example, a metal bolt through the through hole 326 of the small diameter portion 322 of the outer plug 320. The retaining member 330 (FIG. 5) having the above is inserted, and the tip thereof is screwed into the screw hole 313 of the inner plug 310. Thereby, the inner plug 310 can be fixed in the outer plug 320. Accordingly, the inner plug 310 is fixed on the rear end side with respect to the small diameter portion 322 of the outer plug 320, and the small diameter portion 322 of the outer plug 320 protrudes on the front end side with respect to the inner plug 310. At this time, the first contactor 312 is brought into contact with the inner peripheral surface of the outer plug 320, whereby the cable conductor 400, the inner plug 310, and the outer plug 320 are brought into conduction.

  Next, in a state where the outer plug 320 and the inner plug 310 are integrated, the outer plug 320 is inserted into the plug insertion hole 132 a of the inner conductor 13. Thereafter, the stress cone 122 is attached to a predetermined position of the insulating cylinder 14, and a compression device (not shown) for pressing the stress cone 122 is disposed on the rear end side of the stress cone 122, and the rear end side of the compression device. The protective metal fitting 123 is attached and the stress cone 122 is pressed in the distal direction by the compression device, whereby the stopper 324 of the outer plug 320 is engaged with the engaging groove 132b of the inner conductor 13, and the outer plug 320 is engaged with the inner conductor. It is fixed at 13 predetermined positions. At this time, the second contactor 325 comes into contact with the inner conductor 13, whereby the cable conductor 400, the inner plug 310, the outer plug 320, and the inner conductor 13 become conductive. Furthermore, the formation of the terminal connection part (cable connection part) 1 is completed by forming the anticorrosion layer 124 for waterproofing at the rear end part of the protective metal fitting 123.

  In the state where the formation of the terminal connection portion (cable connection portion) 1 is completed using the cable connection device 300, in the present embodiment, as shown by the symbol L1 in FIG. The distance from the shoulder of the inner conductor 13 is reduced, and the thickness of the inner conductor 13 is reduced at this location. However, in the configuration of the present embodiment, since energization is performed on the outer periphery of the small diameter portion 322, even if the inner conductor 13 of the portion indicated by the symbol L1 is thin, the thin portion does not have an adverse effect such as heat generation. . Therefore, according to the configuration of the present embodiment, even when the plugs 310 and 320 having a long compressed length and extending in the axial direction are inserted deeply into the distal end side of the internal conductor 13, the diameter-enlarged portion of the internal conductor 13 as in the prior art. It is not necessary to make a design change that extends 132 in the distal direction.

  In the configuration of the present embodiment, the thickness of the inner conductor 13 at the position corresponding to the small diameter portion 325 of the outer plug 320 shown by the symbol L2 in FIG. 5 has a predetermined thickness (does not adversely affect heat generation when energized). (Thickness of the order) or more. Here, since the diameter of the small diameter portion 322 can be freely designed regardless of the diameter of the cable conductor 400 and the like, if the diameter of the small diameter portion 322 is appropriately set in consideration of the diameter of the inner conductor 13, the small diameter portion 322 is formed. It is easy to set the thickness of the corresponding inner conductor 13 to a predetermined thickness or more.

  As described above, according to the present embodiment, the first current-carrying portion that is compression-connected to the cable conductor 400 and has the first contactor (for example, the multi-ram band) 312 fitted on the outer periphery of the tip portion is provided. An inner plug 310 having a screw hole 313 at the center of the distal end, a large diameter portion 321 into which the inner plug 310 is inserted, and a small diameter portion connected to the large diameter portion 321 so as to extend from the large diameter portion 321 in the distal direction. 322, a second current-carrying portion formed by fitting a second contactor (for example, a multi-ram band) 325 on the outer periphery of the small-diameter portion 322, and a through-hole 326 in the center of the small-diameter portion 322. By providing the outer plug and 320, the cable connecting device 300 that can cope with the change in the compression length of the plug can be realized without greatly changing the design of the inner conductor 13.

  In addition, since the inner plug 310 is connected to the cable conductor 400 by compression, and the outer plug 320 is connected to the inner conductor 13, even if the inner plug 310 is deformed by compression connection, the influence is internally generated. Since the connection with the conductor 13 can be prevented, the connection reliability is improved.

  Further, by providing the small-diameter portion 322 and energizing the small-diameter portion 322, the energized portion can be secured even when the cable conductor 400 has a large diameter.

  Incidentally, in the conventional configuration, as one method corresponding to the increase in the compression length of the plug without greatly changing the design of the inner conductor 13, it is conceivable that the plug is not inserted deeply into the distal end side of the inner conductor. If it does in this way, the whole apparatus must be lengthened to the rear end side, and the enlargement of an apparatus will be caused. In the present embodiment, since the plug is inserted deeply into the distal end side of the internal conductor, the apparatus does not increase in size.

  The above-described embodiments are merely examples of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed as being limited thereto. That is, the present invention can be implemented in various forms without departing from the gist or main features thereof.

  For example, the cable connection device 300 according to the above-described embodiment is connected to an air terminal connection part having an internal conductor using a composite steel pipe or a porcelain steel pipe other than the air terminal connection part using a polymer sleeve. You can also Moreover, it can also connect not to the air termination | terminus termination part but to the gas termination | terminus termination | terminus connection part and the oil termination | terminus connection part which used the epoxy bushing which has an internal conductor. Furthermore, it can also be connected to an intermediate connection such as a prefabricated joint (PJ) or a Y branch joint (YJ). In this case, an electrode that conducts each cable conductor embedded in the epoxy body of PJ or YJ is an internal conductor. In short, the cable connecting device according to the present invention is widely useful as a cable connecting device for connecting a cable conductor to a prefabricated (inner cone type) cable connecting portion.

  Further, in the above-described embodiment, the case where the cable conductor 400 is an aluminum conductor is described as an example in which the compression length needs to be increased and the plug length is increased. However, the cable conductor 400 is not limited to the aluminum conductor.

  The present invention can be applied to a cable connecting device for connecting a cable conductor to a prefabricated cable connecting portion.

1 Termination connection (cable connection)
13 Internal conductor 16 Shield metal fitting 111, 400 Cable conductor 121, 221 Plug 121a, 221a Multi-ram band 312 First contact (multi-ram band)
325 Second contact (multi-ram band)
132, 232 Expanded portion 132a, 232a Plug insertion hole 132b Engaging groove 133 Straight portion 300 Cable connection device 310 Inner plug 311 Insertion hole 313 Screw hole 314 Recessed portion 320 Outer plug 321 Large diameter portion 322 Small diameter portion 323 Insertion hole 324 Stopper 326 Through hole 330 Retaining member

Claims (4)

A cable connection device attached to the tip of a cable conductor,
An inner plug that is compressed and connected to the cable conductor and has a first current-carrying portion formed by fitting a first contact to the outer periphery of the tip;
A large-diameter portion into which the inner plug is inserted, and a small-diameter portion connected to the large-diameter portion so as to extend from the large-diameter portion in the distal direction. An outer plug having a second energization part fitted;
Comprising
The inner plug is fixed on the rear end side from the small diameter portion of the outer plug,
Cable connection device. A screw hole at the center of the tip of the inner plug;
Having a through hole in the center of the small diameter portion of the outer plug;
The inner plug and the outer plug are fixed by fixing a retaining member having a male screw structure at the distal end to the screw hole through the through hole.
The cable connecting device according to claim 1. The cable conductor is an aluminum conductor,
The cable connecting device according to claim 1 or 2. A cable connecting portion having the cable connecting device according to any one of claims 1 to 3,
An inner conductor disposed in the center, and an insulating cylinder provided on the outer periphery of the inner conductor,
The inner conductor has a straight portion and an enlarged diameter portion having a larger outer diameter than the straight portion connected to the rear end of the straight portion,
The large-diameter portion of the outer plug is disposed in the enlarged-diameter portion, and at least a part of the small-diameter portion of the outer plug is disposed so as to enter the straight portion.
Cable connection.

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