JP6404302B2 - Method for assembling terminal connection part of power coaxial cable - Google Patents

Description

  The present invention relates to a method for assembling a terminal connection portion of a power coaxial cable.

  Conventionally, for example, a connection structure shown in Patent Document 1 is known as a terminal connection portion of a power coaxial cable.

  The power coaxial cable has a configuration in which at least an inner conductor, an inner insulator, an outer conductor, an outer insulator, a cable shielding layer, and a cable sheath are formed concentrically from the center.

  A terminal connection portion (a terminal connection portion, an intermediate connection portion, or the like) is provided at the end of the coaxial cable for power so as to send electric power to each of the inner conductor and the outer conductor.

  The terminal connection part of Patent Document 1 insulates the terminal part of the cable manufactured by stripping the end part of the coaxial cable for power at a predetermined length to expose each layer and attaching connection parts such as a stress cone and a compression device. It is configured by mounting on the coaxial cable terminal receiving part of the unit. In addition, the predetermined length at the time of stepping is set corresponding to a connection component or the like attached to the stepping portion.

  The insulating unit includes a conductor lead bar, a buried electrode, an insulating part, a shielding layer, and the like. The insulating part is a hollow molded body and has a coaxial cable terminal receiving part. The conductor lead bar is connected to the coaxial cable terminal receiving portion at one end portion (rear end portion), and is provided at the insulating portion so that the other end portion (tip portion) penetrates the insulating portion and is exposed to the outside. . The conductor lead bar is connected to the inner conductor of the power coaxial cable to be mounted. The buried electrode is buried in the insulating portion, and is connected to the outer conductor of the power coaxial cable via the outer conductor connecting part attached to the outer peripheral surface of the outer conductor of the power coaxial cable as a connecting part. In addition, an electric field relaxation component including a stress cone for controlling the electric field between the inner conductor and the outer conductor is mounted on the outer peripheral surface of the inner insulator exposed by stripping. On the rear end side of the stress cone, a pressing metal fitting of a compression device that presses the stress cone from the rear end side is disposed.

  The outer conductor connecting component has a hollow frustum shape whose outer surface is reduced in diameter toward the rear end side, and is along the outer circumferential surface of the conductive frustum-shaped outer conductor fixing bracket and the outer frustum-shaped conical shape of the outer conductor fixing bracket. The outer conductor fixing ring has an inner peripheral surface.

When assembling the terminal connecting portion, the outer conductor is disposed on the outer surface of the outer conductor fixing bracket and the outer conductor on the tapered outer surface of the hollow frustoconical portion on the rear end side of the outer conductor fixing bracket. It is sandwiched between outer conductor fixing rings. The outer conductor is fixed to the outer conductor fixing ring and the outer conductor fixing bracket by fastening the outer conductor fixing ring and the outer conductor fixing bracket with a plurality of bolts arranged so as to surround the outer conductor.
The external conductor is electrically connected to the embedded electrode via the external conductor connecting parts (external conductor fixing ring and external conductor fixing metal fitting) thus mounted.

  When fixing the external conductor to the external conductor connection component at this terminal connection part, strip the tip of the power coaxial cable with a predetermined length to expose each layer, and then connect the exposed external conductor to the external conductor connection. Before being fixed to the component, it is processed so as to have a shape (also referred to as a fixed shape) corresponding to the outer surface of the hollow frustoconical outer conductor fixing metal fitting. The fixed shape is the shape when the outer conductor is fixed by being sandwiched between the outer conductor fixing ring and the outer conductor fixing bracket, and is fixed when the outer conductor is fixed with the outer conductor fixing ring and the outer conductor fixing bracket. The shape is easy to perform.

Processing of the conventional fixed shape with respect to the outer conductor will be described with reference to FIGS.
In the power coaxial cable 2 shown in FIG. 1, first, in order from the distal end side, an inner conductor 21a, an inner insulator 21c, an inner semi-conductive outer semiconductive layer 21d, an outer conductor 22a, an outer insulator 22c, and an outer insulating outer semi-conductor. The conductive layer 22d and the cable shielding layer 23 are stripped so as to be exposed. Since the outermost layer of the power coaxial cable 2 has the cable sheath 25, the rear end side of the cable shielding layer 23 exposed by stripping is covered with the cable sheath 25.
Next, the outer conductor 22a is radially opened at the tip 2a of the power coaxial cable 2.

  Next, as shown in FIG. 2, the outer conductor fixing bracket 331A disposed on the front end portion 2a of the power coaxial cable 2 is moved from the front end side to the rear end side of the power coaxial cable 2 to The hollow frustoconical part on the rear end side of 331A is inserted so as to reach the vicinity of the base of the open outer conductor 22a. Next, the external conductor 22a is strongly struck with a hammer H or other striking tool H on the external conductor fixing bracket 331A so as to conform to the shape of the external conductor fixing bracket 331A, thereby changing the shape of the external conductor 22a. As a result, the outer conductor 22a is deformed along the inclined outer surface of the hollow frustoconical portion of the outer conductor fixing bracket 331A and shaped into a fixed shape. Next, an outer conductor fixing ring (not shown) arranged in advance on the rear end side of the power coaxial cable 2 is moved to the front end side and arranged on the outer conductor 22a, and the outer conductor fixing ring, the outer conductor fixing bracket 331A, Are fastened with a plurality of bolts, and the outer conductor 22a is fixed so as to be sandwiched between the outer conductor connecting parts, that is, the outer conductor fixing ring and the outer conductor fixing bracket 331A. Thereby, the outer conductor 22a is connected to the outer conductor connecting component.

JP 2014-50223 A

However, the connection method of the outer conductor in the method of assembling the terminal connection portion of the power coaxial cable described above has the following problems (1) to (3).
(1) In order to sandwich the outer conductor 22a on the outer conductor fixing bracket 331A by the outer conductor fixing ring and the outer conductor fixing bracket 331A, the outer conductor 22a is hammered on the outer conductor fixing bracket 331A as shown in FIG. It is necessary to hit with H etc. strongly. Therefore, the outer conductor fixing bracket 331A under the outer conductor 22a struck by a hammer H or the like collides with the outer semiconductive layer 21d on the cable insulator (inner insulator) 21c, and the outer semiconductive layer 21d It may cause damage such as dents, which may reduce insulation performance.
(2) When the external conductor fixing bracket 331A is inserted into the inner surface of the external conductor 22a and then the external conductor 22a is struck with a hammer H or the like, the external conductor 22a generally formed of metal (for example, copper) and the external The conductor fixing metal fitting 331A comes into contact. Due to the contact between the metals, metal powder such as copper powder is generated and easily adheres to the power coaxial cable 2. For this reason, there exists a possibility that the insulation performance in the terminal connection part of the coaxial cable 2 for electric power may fall.
(3) When the outer conductor 22a cannot be formed in a shape that can be sandwiched between the outer conductor fixing ring and the outer conductor fixing bracket 331A, the outer conductor fixing ring and the outer conductor fixing bracket 331A disposed on the outer periphery of the outer conductor 22a If the outer conductor 22a is sandwiched and tightened with a fixing bolt, the torque for tightening the fixing bolt is not applied and the assembly is not easy. In this case, the fixing bolt and the outer conductor fixing ring are removed from the outer conductor 22a, and again, as shown in FIG. 2, the outer conductor 22a is struck with a resin hammer H so that it follows the outer conductor fixing bracket 331A. It is necessary to perform a process of re-forming and reassembling the shape of the outer conductor 22a.

  The object of the present invention is to easily attach the shape of the outer conductor when the outer conductor of the coaxial cable for electric power is fixed to the outer conductor connecting component, so that the outer conductor is fixed when the outer conductor is fixed. A power coaxial cable that can be easily and suitably connected to a connection part to improve the connection workability of an outer conductor and easily assemble a terminal connection portion of a power coaxial cable having stable insulation performance. It is to provide a method for assembling a terminal connection unit.

The method of assembling the terminal connection portion of the power coaxial cable according to the present invention is as follows.
In order from the center, at least the inner conductor, the inner insulator, the outer conductor, the outer insulator, and the end portion of the power coaxial cable in which the cable shielding layer is formed concentrically, step at least the inner conductor, An inner insulator, an outer conductor connecting component that exposes the outer conductor and is electrically connected to the outer conductor, a first electric field relaxation component for controlling an electric field between the inner conductor and the outer conductor, and Attaching a second electric field relaxation component for controlling the electric field between the outer conductor and the cable shielding layer to form a cable terminal portion;
The cable terminal portion is formed so as to surround an outer peripheral surface of an embedded electrode electrically connected to the inner conductor connecting portion and the outer conductor connecting component electrically connected to the inner conductor, and is rigid. In the method of assembling the terminal connection portion of the power coaxial cable to be mounted and assembled to the coaxial cable terminal receiving portion of the insulating portion made of the insulating material,
The outer conductor connecting component has a first fixing member and a second fixing member that are clamped and fixed in a state where the outer conductor is pressed with a specified torque via a fixing bolt,
An outer to step from the insert inside the bent root habit jig outer conductor, the outer conductor with the habit bending extends in a radial direction at the root portion, the bending coaxial cable wherein the habit jig power,
By applying a torque equivalent to the specified torque to the first fixing member and the second fixing member arranged so as to sandwich the outer conductor via the tightening bolt of the tightening jig, Forming the outer conductor into a fixed shape fixed by the first fixing member and the second fixing member ;
Removing the clamping jig from the coaxial cable for electric power, and fixing the outer conductor between the first fixing member and the second fixing member by the fixing bolt . .

  According to the present invention, before fixing the outer conductor of the power coaxial cable to the outer conductor connecting component, it is possible to easily attach the shape of the outer conductor when the outer conductor is fixed without being hit with a hammer. Therefore, it is possible to easily and suitably connect the outer conductor to the outer conductor connecting part to improve the connection workability of the outer conductor, and the terminal connection portion of the power coaxial cable having stable insulation performance is provided. Can be easily assembled.

It is a figure explaining the process of opening the outer conductor of the coaxial cable for electric power in the terminal connection part of the conventional coaxial cable for electric power. It is a figure explaining the process which inserts an outer conductor fixing metal fitting inside the outer conductor of a power coaxial cable, and makes an outer conductor follow the outer surface of an outer conductor fixing metal fitting in the terminal connection part of the conventional power coaxial cable. It is sectional drawing which shows the terminal connection part of the coaxial cable for electric power assembled by applying the assembly method of the terminal connection part of the coaxial cable for electric power. FIG. 4 is an enlarged view of a portion indicated by X in FIG. 3. It is a figure explaining the process of attaching a bending hook to the outer conductor of a power coaxial cable in the assembly method of the terminal connection part of the power coaxial cable which concerns on this invention. In the method of assembling the terminal connection portion of the power coaxial cable according to the present invention, the step of inserting the outer conductor fixing bracket inside the outer conductor of the power coaxial cable and inserting the direct lead jig inside the outer conductor fixing bracket FIG. It is a figure explaining the process of pinching | interposing an outer conductor with an outer conductor fixing metal fitting and an outer conductor fixing ring using the fastening jig | tool in the assembly method of the terminal connection part of the coaxial cable for electric power which concerns on this invention. FIG. 8 is an exploded view of the fastening jig shown in FIG. 7. It is a fragmentary sectional view which shows the state which the front-end | tip part of the conventional external conductor fixing metal fitting deform | transformed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, the terminal connection part of the power coaxial cable assembled by the method of assembling the terminal connection part of the power coaxial cable according to the present embodiment will be described.

<Overall configuration of terminal connection part of power coaxial cable>
FIG. 3 is a cross-sectional view showing the terminal connection portion of the power coaxial cable assembled by applying the method of assembling the terminal connection portion of the power coaxial cable according to the embodiment. In the following description, in FIG. 3, the upper side is referred to as the front end side, and the lower side is referred to as the rear end side.

  The terminal connection portion 1 of the power coaxial cable shown in FIG. 3 is an in-gas termination connection portion for connecting the power coaxial cable 20 to a power device such as a gas insulated switchgear or a transformer.

  As shown in FIG. 3, the terminal connection portion 1 of the power coaxial cable is configured by mounting the power coaxial cable 20 and the power single-core cable 40 on the insulating unit 10.

  Here, the power single-core cable in the present application is for distinguishing from the power coaxial cable, and includes a so-called triplex cable (for example, a CVT cable).

  The power coaxial cable 20 includes, in order from the center, an internal conductor 21a, an internal semiconductive layer (not shown) for internal insulation, an internal insulator 21c, an external semiconductive layer 21d for internal insulation, an external conductor 22a, and an internal semiconductive layer for external insulation. A configuration in which a conductive layer (not shown), an external insulator 22c, an external semiconductive layer 22d for external insulation, a cable shielding layer 23, a pressing tape (not shown), and a cable sheath 25 (here, a vinyl sheath) are formed concentrically. Have

  The power coaxial cable 20 is a so-called high voltage coaxial cable in which an inner insulator 21c and an outer insulator 22c are made of crosslinked polyethylene.

  A current with a first voltage (for example, 66 kV) flows through the inner conductor 21a, and a current with a second voltage (for example, 11 kV) flows through the outer conductor 22a to transmit power. The first voltage applied to the inner conductor 21a is higher than the second voltage applied to the outer conductor 22a. Further, the cable shielding layer 23 is set to the ground potential.

  The power single-core cable 40 includes, in order from the center, a cable conductor 41, an internal semiconductive layer (not shown), an insulating layer 42, an external semiconductive layer 43, a cable shielding layer 44, a pressing tape (not shown), and a cable sheath 45. (In this case, vinyl sheath) and the like. The power single-core cable 40 is a CV cable for 11 kV, for example, in which the insulating layer 42 is made of crosslinked polyethylene. One end of the power single-core cable 40 is connected to the insulating unit 10, and the other end is connected to a power device such as a gas-insulated switchgear or a transformer or an air terminal connection (11 kV side).

  The ends of the coaxial cable for power 20 and the single-core cable for power 40 are stepped to a predetermined length to expose each layer, and a connecting part such as a stress cone or a compression device is attached to produce a terminal portion of the cable. .

  The insulating unit 10 includes a conductor lead bar (internal conductor connecting portion) 11, an embedded electrode 12, an insulating portion 13, a shielding layer 14, and the like.

  Further, the insulating unit 10 has a mounting flange 15 at a lower end portion of a bushing head portion 13c to be described later, and this mounting flange 15 is attached to a power device installation plate 70 via a sealing material (not shown) such as an O-ring. By bolting, the bushing head 13c is disposed in an airtight manner in a state where the bushing head 13c is disposed inside the power device.

  The insulating part 13 is a hollow molded body made of a hard insulating material such as an epoxy resin. The insulating part 13 includes a coaxial cable terminal receiving part 13a for mounting the terminal part of the power coaxial cable 20, a single core cable terminal receiving part 13b for mounting the terminal of the power single cable 40, and a power device. It has a bushing head 13c to be placed inside.

  In FIG. 3, the single-core cable terminal receiving part 13b is formed in the part branched from the part in which the coaxial cable terminal receiving part 13a is formed. The bushing head portion 13c is formed on the distal end side of the portion where the coaxial cable terminal receiving portion 13a is formed, and has a shape in which a cylindrical portion and a truncated cone portion are continuously provided.

  The conductor lead bar 11 is made of a metal material suitable for energization such as a copper alloy. A conductor insertion portion 11 a for electrically connecting the inner conductor 21 a of the power coaxial cable 20 is formed at the rear end portion of the conductor lead bar 11.

  The conductor lead-out bar 11 is embedded in the insulating portion 13 so that the conductor insertion portion 11a and the coaxial cable end receiving portion 13a of the insulating portion 13 are connected to each other and the distal end portion 11b penetrates the insulating portion 13 and is exposed to the outside. Is done. The leading end portion 11b of the conductor lead bar 11 is connected to a conductor portion (not shown) in the power device.

  The embedded electrode 12 is made of a metal material suitable for energization such as a copper alloy. The embedded electrode 12 is embedded in the insulating portion 13 so as to connect the coaxial cable terminal receiving portion 13a and the single-core cable terminal receiving portion 13b.

  The conductor lead bar 11, the embedded electrode 12, and the insulating portion 13 are integrally formed by molding an epoxy resin.

  The shielding layer 14 of the insulating unit 10 is a conductive layer formed on the outer surface of the insulating portion 13. When the shielding layer 14 is grounded, the outer surface of the insulating unit 10 is held at the ground potential. Thereby, the electric field stress in the insulating part 13 is relieved and external leakage of the electric field is prevented.

  The shielding layer 14 is formed, for example, by applying a conductive paint to the outer surface of the insulating portion 13. In the case where the shielding layer 14 is formed by applying a conductive paint, the shielding layer 14 can be easily formed, so that the degree of freedom in designing the shape of the insulating portion 13 is increased.

  The shielding layer 14 of the insulating unit 10 and the cable shielding layer 23 of the power coaxial cable 20 or the cable shielding layer 44 of the power single-core cable 40 are cut off by providing an edge cut portion. By providing this edge cut portion, the cable shielding layers 23 and 44 can be protected from an open / close surge or a lightning surge of the power equipment.

  The edge cut portion may be formed by an insulating tube made of epoxy resin, but as shown in FIG. 3, the shielding layer 14 is not formed on the end portions 13d and 13e of the insulating portion 13 (here, no conductive paint is applied). Thus, one end portion 13 d of the insulating portion 13 becomes an edge cutting portion for cutting the cable shielding layer 23 (here, the metal fitting flange 342) and the shielding layer 14 of the power coaxial cable 20. In addition, the other end 13e of the insulating portion 13 includes a cable shielding layer 44 (here, the cable protection metal fitting 53 that is in contact with the compression device 52) of the power single-core cable 40 and an edge cutting portion that cuts off the shielding layer 14. Become.

  This eliminates the need for an insulating cylinder for edge cutting, reduces the number of parts, improves workability during assembly, and eliminates the need for an insulating cylinder, so that it can be compactly formed in the longitudinal direction as a terminal connection part, and cable processing Since the length is short, it is more preferable.

  The terminal portion of the power coaxial cable 20 that has been subjected to the step stripping process and to which a predetermined connection component is attached is attached to the coaxial cable terminal receiving portion 13a in a slip-on manner. Thereby, the power coaxial cable 20 can be easily connected to the insulating unit 10, and the construction time can be shortened.

  Specifically, a conductive conductor connection sleeve 31 suitable for energization made of, for example, copper, aluminum, copper alloy, or aluminum alloy is provided on the inner conductor 21a at the stepped end of the power coaxial cable 20. Installed by compression. A conductor contact (for example, a multi-ram band) for allowing the terminal portion of the power coaxial cable 20 to be inserted into and removed from the insulating unit 10 is disposed on the outer periphery of the conductor connection sleeve 31. It is attached to the insertion portion 11a so as to be insertable / removable (slip-on method).

  Thus, when the power coaxial cable 20 is attached to the insulating unit 10 by the slip-on method, the cable processing length can be shortened and the cable can be easily attached and detached, so that the construction time can be greatly reduced.

  A first electric field relaxation component 32 for controlling the electric field between the inner conductor 21 a and the outer conductor 22 a is attached to the outer peripheral surface of the inner insulator 21 c of the power coaxial cable 20. Here, the first electric field relaxation component 32 includes a first stress cone 321 and a first compression device CU1. The first compression device CU1 presses the first stress cone 321 from the rear end side, and here is configured by a pressing metal 322, a spring 323, and a pressing metal pipe 324.

  A first stress cone 321 is attached to the outer peripheral surface of a portion extending from the internal insulator 21c to the external semiconductive layer 21d for internal insulation. The first stress cone 321 includes an insulating portion on the tip side made of an insulating rubber material (for example, ethylene propylene rubber (EP rubber) or silicone rubber) and a semiconductive rubber material (for example, semiconductive ethylene). A semiconductive portion on the rear end side made of propylene rubber (EP rubber) or silicone rubber). The insulator portion and the semiconductor portion are integrally formed by molding. The distal end portion (insulator portion) of the first stress cone 321 has a shape corresponding to the coaxial cable terminal receiving portion 13a of the insulating portion 13 (here, a tapered shape). The tip of the semiconductive portion has a bell mouth shape having a circular arc cross section in order to reduce the electric field.

  A push fitting 322 is disposed on the rear end side of the first stress cone 321. The front end portion of the press fitting 322 is formed in a trumpet shape whose inner diameter increases toward the front end side corresponding to the outer peripheral surface on the rear end side of the first stress cone 321 (the outer peripheral surface of the semiconductive portion). The

  A plurality of recesses for accommodating a coiled spring 323 are provided on the circumference at the rear end portion of the press fitting 322, and the springs 323 are respectively disposed in the recesses, and a press fitting pipe 324 is provided at the rear end side of the spring 323. Be placed. A partition piece 324a projecting radially inward is formed in the vicinity of the distal end portion of the pressing metal pipe 324, and the rear end portion of the spring 323 is supported by the partition piece 324a.

  The rear end portion of the pressing metal pipe 324 extends to the rear end portion of the embedded electrode 12. The flange surface of the rear end portion of the pressing metal pipe 324 is brought into contact with the rear end surface (stepped portion) of the embedded electrode 12 and fixed by a plurality of bolts V1, whereby the first stress cone 321 is insulated from the insulating portion 13. It is fixed in a pressed state on the inner peripheral surface of the (coaxial cable terminal receiving portion 13a). The pressing metal pipe 324 is electrically connected to the embedded electrode 12. Further, the inner diameter of the first stress cone 321 is formed smaller than the outer diameter of the cable (the outer diameter of the internal insulator 21c).

  An outer conductor connecting component 33 is attached to the outer peripheral surface of the outer conductor 22 a of the power coaxial cable 20. The external conductor connecting component 33 includes a conductive external conductor fixing metal fitting 331 and an external conductor fixing ring 332 that are suitable for energization made of, for example, copper, aluminum, a copper alloy, or an aluminum alloy.

FIG. 4 is an enlarged view of a portion indicated by X in FIG.
The outer conductor fixing metal fitting 331 shown in FIG. 3 and FIG. 4 is formed in a hollow truncated cone shape whose diameter is reduced toward the rear end side. The outer conductor fixing metal fitting 331 is disposed on the inner periphery on the rear end side of the partition piece 324a of the pressing metal pipe 324, and is a multi-surface contact type conductor contactor 37 (here, a multi-contact type contactor 37) disposed on the outer peripheral surface of the outer conductor fixing metal fitting 331. It is electrically connected to the presser fitting pipe 324 via a ram band (see FIG. 4, not shown in FIG. 3). In the present embodiment, the outer conductor fixing metal fitting 331 includes a hollow truncated cone part 3311 that decreases in diameter toward the rear end side, and a circle that protrudes from the outer periphery of the hollow truncated cone part 3311 on the distal end side of the hollow truncated cone part 3311. And an annular flange portion 3313. Bolt holes into which a plurality of bolts (fixing bolts) V2 are screwed are formed in the flange portion 3313 in parallel with the axial direction in the circumferential direction. The conductor contactor 37 is a large number of ribbon-like leaf spring assemblies, and is fitted into an annular groove formed on the outer peripheral surface of the flange portion 3313 and arranged on the circumference. The conductor contactor 37 includes a plurality of contacts in the circumferential direction that protrude in the radial direction from the outer peripheral surface of the flange portion 3313 and that can protrude and retract in the radial direction by elastic deformation. The flange portion 3313 has a chamfered portion 3315 on the outer peripheral edge on the tip side. The outer conductor fixing bracket 331 has a chamfered portion 3315 at which the corner on the tip side, that is, the angle at which the outer peripheral surface of the flange portion 3313 and the tip side surface of the flange portion 3313 (tip surface of the outer conductor fixing bracket 331) intersect. There is no. The chamfered portion 3315 may be an R chamfer as in the embodiment of FIGS. 3 and 4 or a C chamfer.

  The outer conductor 22a is disposed along the tapered outer surface (specifically, the outer surface of the hollow truncated cone portion 3311) on the rear end side of the outer conductor fixing bracket 331, and the outer conductor fixing ring 332 is fitted from the outside. The outer conductor fixing ring 332 is fixed to the outer conductor fixing bracket 331 by fixing the outer conductor fixing bracket 331 with a plurality of bolts V2. The outer conductor 22a is nipped and fixed while being pressed by the outer conductor fixing metal fitting 331 (first fixing member) and the outer conductor fixing ring 332 (second fixing member). The outer conductor 22a is electrically connected to the embedded electrode 12 via the outer conductor fixing metal fitting 331 and the pressing metal pipe 324.

  When the external conductor 22a and the embedded electrode 12 are electrically connected, soldering or welding is not performed, so that the external conductor 22a and the external conductor connecting component 33 can be easily separated during disassembly. Further, the external conductor connecting component 33 can be reused.

  A second electric field relaxation component 34 for controlling the electric field between the outer conductor 22 a and the cable shielding layer 23 is attached to the outer peripheral surface of the outer insulator 22 c of the power coaxial cable 20. Here, the second electric field relaxation component 34 includes a second stress cone 341 and a second compression device CU2. The second compression device CU <b> 2 presses the second stress cone 341 from the rear end side, and here is constituted by a pressing metal flange 342.

  A second stress cone 341 is attached to the outer peripheral surface of the portion extending from the external insulator 22c to the external insulating external semiconductive layer 22d. A stopper 35 is interposed between the second stress cone 341 and the rear end portion of the first compression device CU1 (here, the metal fitting pipe 324). The second stress cone 341 has substantially the same configuration as the first stress cone 321, although the shape is different. That is, the second stress cone 341 has an insulator portion on the front end side and a semi-conductor portion on the rear end side, and the outer periphery of the tip portion (insulator portion) of the second stress cone 341 It has a shape corresponding to the rear end (here, a tapered shape). The tip of the semiconductive portion of the second stress cone 341 has a bell mouth shape whose tip is arc-shaped in cross section in order to relax the electric field.

  On the rear end side of the second stress cone 341, a pressing metal flange 342 is disposed. The second stress cone 341 is fixed in a state of being pressed against the inner peripheral surface of the insulating portion 13 by bringing the front end surface of the pressing metal flange 342 into contact with the rear end surface of the insulating portion 13 and fixing with the bolt V3. . In addition, the inner diameter of the second stress cone 341 is smaller than the outer diameter of the cable (the outer diameter of the external insulator 22c), and the second stress cone 341 and the power coaxial cable 20 are securely in close contact due to the difference in diameter.

  The cable shielding layer 23 of the power coaxial cable 20 is connected to the pressing metal flange 342. The cable shielding layer 23 is connected to the ground potential through the presser flange 342.

  A protective metal fitting 61 is attached to the rear end side of the pressing metal flange 342, and an anticorrosion layer 62 is formed from the rear end portion of the protective metal fitting 61 to the cable sheath 25 of the power coaxial cable 20.

  Further, the terminal portion of the power single-core cable 40 subjected to the stripping process is attached to the single-core cable terminal receiving portion 13b. Specifically, a connecting component 50 including a stress cone 51, a compression device 52 (here, a type having a shaft), and the like is attached to the distal end portion of the power single-core cable 40. The cable conductor 41 and the embedded electrode 12 are electrically connected by connecting the terminal portion of the power single-core cable 40 to which the connecting component 50 is attached to the single-core cable terminal receiving portion 13b (inserted in FIG. 3). Is done. Further, the cable shielding layer 44 of the power single-core cable 40 is connected to the ground potential via, for example, the compression device 52 and the cable protection fitting 53.

  Note that the configuration of the terminal portion of the power single-core cable 40 may be a known connection method, and is not limited to that described in the present embodiment.

  As described above, the terminal connection portion 1 of the power coaxial cable according to the embodiment includes the conductor lead bar 11 electrically connected to the inner conductor 21a of the power coaxial cable 20 and the outer conductor of the power coaxial cable 20. The embedded electrode 12 electrically connected to 22a, the conductor extraction rod 11 and the embedded electrode 12 are integrally formed with the conductor extraction rod 11 and the embedded electrode 12 so as to surround the outer peripheral surface of the conductor extraction rod 11 and the power coaxial. An insulating portion 13 made of a hard insulating material having a coaxial cable end receiving portion 13a for mounting the cable end portion of the cable 20 and a shielding layer 14 formed on the outer surface of the insulating portion 13 are provided. The insulating unit 10 is constituted by the conductor lead bar 11, the embedded electrode 12, the insulating part 13 having the coaxial cable terminal receiving part 13a, and the shielding layer 14. The external conductor connection component 33, the first electric field relaxation component 32 that is attached to the distal end side of the external conductor connection component 33 and controls the electric field between the internal conductor 21a and the external conductor 22a, and the external conductor connection component 33 is attached to the coaxial cable terminal receiving part 13a. The cable terminal part is attached to the rear end side 33 and is attached with the second electric field relaxation component 34 for controlling the electric field between the outer conductor 22a and the cable shielding layer 23. (So-called inner cone type).

  Further, in the terminal connection portion 1 of the power coaxial cable, the inner conductor 21a of the power coaxial cable 20 and the conductor lead bar 11 (inner conductor connection portion) are electrically connected in a sealed space in the insulating unit 10, Further, the outer conductor 22 a of the power coaxial cable 20 and the cable conductor 41 of the power single-core cable 40 are electrically connected via the embedded electrode 12. A portion where the inner conductor 21a of the power coaxial cable 20 and the conductor lead bar 11 are connected is a first high voltage portion, and the outer conductor 22a of the power coaxial cable 20 and the cable conductor 41 of the power single-core cable 40 are connected. The part to be connected becomes the second high-pressure part. All of the first high-voltage part and the second high-voltage part are covered with the insulating part 13 of the insulating unit 10 and are insulated from the outside. A first voltage is applied to the first high voltage section, and a second voltage is applied to the second high voltage section. In the embodiment, a voltage of 66 kV is applied to the first high voltage part, and a voltage of 11 kV is applied to the second high voltage part. The terminal connection part 1 of the power coaxial cable has a completely sealed structure in which the high-voltage part and the charging part are covered with the shielding layer 14 and are not exposed, so it can effectively prevent human injury (electric shock) and fire due to contact. Excellent safety.

  Moreover, in the terminal connection part 1 of the power coaxial cable, since the terminal of the power coaxial cable can be inserted / removed by using the slip-on method among the inner cone types, it can be easily inserted / removed.

<Assembly Method of Terminal Connection 1 of Power Coaxial Cable>
5, FIG. 6 and FIG. 7 are diagrams for explaining a connection process between the outer conductor of the power coaxial cable and the outer conductor fixing metal fitting in the method of assembling the terminal connection portion of the power coaxial cable according to the present invention. FIG. 8 is an exploded view of the fastening jig shown in FIG.

  First, in order from the center, internal conductor 21a, internal semiconductive layer for internal insulation (not shown), internal insulator 21c, external semiconductive layer 21d for internal insulation, external conductor 22a, internal semiconductive layer for external insulation (not shown). A front end portion 20a of the power coaxial cable 20 having a configuration in which an external insulator 22c, an external semiconductive layer 22d for external insulation, a cable shielding layer 23, a pressing tape (not shown), and a cable sheath 25 are formed concentrically. Is stripped from the tip side by a predetermined length. Thereby, in the front-end | tip part 20a of the coaxial cable 20 for electric power, from the front end side, the internal conductor 21a, the internal insulator 21c, the external semiconductive layer 21d for internal insulation, the external conductor 22a, the external insulator 22c, the external semiconductive for external insulation The layer 22d and the cable shielding layer 23 are exposed to the outside. When exposing (leading out) the outer conductor 22a, the outer conductor 22a is cut so as to be exposed for a predetermined length. Next, the conductor connection sleeve 31 is inserted over the inner conductor 21a at the stepped end of the power coaxial cable 20, and the wedge 36 is driven into the center of the inner conductor 21a using a punch or the like. After confirming that the inner conductor 21a has been inserted all the way into the conductor connection sleeve 31, the conductor connection sleeve 31 is formed in a concave shape at the center in the longitudinal direction of the conductor connection sleeve 31 using a dedicated hexagonal die (not shown). By being compressed on the rear end side from the groove, it is compression-connected to the internal conductor 21a. At the time of compression work, care is taken so that the gap between the conductor connecting sleeve 31 attached to the inner conductor 21a and the insulator does not widen. By driving the wedge 36, it is possible to make it difficult for the conductor connection sleeve 31 after compression to come out of the inner conductor 21a. A conductor contact (not shown) such as a multi-ram band is attached to the outer periphery on the tip side from the groove of the concave portion of the conductor connection sleeve 31.

Next, the protective metal fitting 61 (see FIG. 3) in a state where an O-ring (not shown) is mounted in a groove formed on the front end surface of the protective metal fitting 61 is connected from the front end of the power coaxial cable 20 to the power coaxial cable 20. Then, the power coaxial cable 20 is positioned on the rear end side of the front end portion 20 a, that is, on the cable sheath 25. Thereafter, the cable shielding layer 23 is grounded. Specifically, a plurality of braided wires (here, four) are soldered to the cable shielding layer 23 with an annealed copper wire to form a plurality of braided wires connected to the cable shielding layer 23. Thereafter, the second electric field relaxation component 34 is positioned from the front end side of the power coaxial cable 20 to the rear end side of the power coaxial cable 20. Specifically, the second compression device CU2 (here, the cylindrical pressing metal flange 342) and the second stress cone 341 are sequentially passed through the front end of the power coaxial cable 20 and the rear end of the power coaxial cable 20 is placed. Position on the side. The second stress cone 341 is formed on the distal end portion 20a of the power coaxial cable 20 after applying a lubricant such as silicone oil to the inner peripheral surface of the second stress cone 341 and the surface of the external insulator 22c. Then, the cable is once inserted to the front of the cable shielding layer 23.
Next, the power coaxial cable 20 is inserted from the tip in the order of the stopper 35 and the outer conductor fixing ring 332.

  After each component inserted into the power coaxial cable 20 is cured with a resin (here, polyethylene) sheet or the like, the outer conductor 22a is fixed with the outer conductor fixing ring 332 and the outer conductor fixing bracket 331. Deform.

  When the outer conductor 22a is fixed by the outer conductor fixing ring 332 and the outer conductor fixing bracket 331, first, at the distal end portion 20a, the root of the outer conductor 22a, which is a plurality of wires, that is, the outer conductor exposed at the distal end portion 20a. The rear end portion of 22a is bound and fixed from the outer surface side with a wire material such as an annealed copper wire. Next, a step of attaching a bending ridge to the base of the external conductor 22a (base bending ridge step) is performed. This process is shown in FIG. In the root bending process, first, the outer conductor 22a exposed from the base bound with the wire is radially opened, that is, the distal end side of the outer conductor 22a is deformed in a direction away from the axis of the power coaxial cable rather than the proximal end side. Let In the present embodiment, the outer conductor 22a is spirally wound on the inner insulating outer semiconductive layer 21d, so that the outer conductor 22a is opened outward in the winding direction.

Next, the bending rod jig 71 is inserted to the inner base of the outer conductor 22a on the inner insulating outer semiconductive layer 21d. Thereafter, the bending rod jig 71 is pressed and the outer surface of the external conductor 22a is lightly struck with a resin hammer H to attach a bending rod.
The bending rod jig 71 is made of resin, and is formed of, for example, polyacetal (also called POM) or MC nylon (registered trademark of Quadrant Polypenco Japan). The bending rod jig 71 has an annular shape with a cut at one place on the outer surface, and the bending rod jig 71 can be slightly expanded in the radial direction.

  As a result, the outer conductor 22a has a bending ridge that extends in the radial direction at the root portion, and has a shape that extends from the root curved in the radial direction toward the distal end side. If the outer conductor 22a is bent, the bending hook jig 71 is removed from the power coaxial cable 20.

  As shown in FIG. 6, the outer conductor fixing bracket 331 is inserted into the power coaxial cable 20, and the outer conductor fixing bracket 331 is linearly formed in the axial direction on the inner side of the outer conductor 22a. The step of inserting and inserting the outer conductor fixing bracket direct extraction jig 81 into the outer conductor fixing bracket 331 is performed.

  In this step, an external conductor fixing bracket direct extraction jig (hereinafter also referred to as “direct extraction jig”) 81 prepared in advance is used.

The direct lead jig 81 is provided around the outer semiconductive layer 21d for internal insulation in order to extend the portion of the outer semiconductive layer 21d for internal insulation to which the outer conductor fixing metal fitting 331 is attached in a straight line in the axial direction. Be placed. The direct-out jig 81 is formed in a cylindrical shape that can be disposed on the inner semi-conductive outer semiconductive layer 21d. A part of the direct lead jig 81 is arranged on the inner peripheral side of the front end side of the outer conductor fixing metal fitting 331, and the outer conductor fixing metal fitting 331 is concentric with the power coaxial cable 20 at the front end portion 20 a of the power coaxial cable 20. It is used when mounting in a shape.
The direct-out jig 81 has a larger outer diameter at one end (the rear end side of the power coaxial cable 20) than the direct-out main body 811 at the other end (the front end side of the power coaxial cable 20). A diameter portion 812 is provided. The direct feed jig 81 is made of a resin such as polyacetal (also called POM) or MC nylon (registered trademark of Quadrant Polypenco Japan Co., Ltd.). The main body portion 811 and the large-diameter portion 812 are provided continuously. The direct-out jig 81 may be formed in a two-part structure that is vertically divided by a plane along the longitudinal direction. In this case, because of the split structure, it is easy to match the outer diameter of the power coaxial cable 20, and a cylindrical direct access jig is secured by winding a tape around the outer periphery of the direct access body 811. 81 is formed.

  The outer diameter of the large-diameter portion 812 on one end side is determined when the direct-out jig 81 is positioned on the power coaxial cable 20 with the large-diameter portion 812 side facing the rear end side of the power coaxial cable 20. In addition, the diameter engages with a stepped portion 3312 (see also FIG. 3) inside the outer conductor fixing metal fitting 331. Further, the inner diameter of the direct lead jig 81 is smaller than the inner diameter on the rear end side (cable sheath 25 side) from the stepped portion 3312 of the external conductor fixing metal fitting 331.

  The outer conductor fixing metal fitting 331 is inserted into the power coaxial cable 20 including the outer conductor 22a with the bending wrinkle in the root bending ironing process, and the outer conductor fixing metal fitting 331 is linearly formed in the axial direction on the inner base of the outer conductor 22a. Then, as shown in FIG. 6, the direct delivery jig 81 is inserted into the power coaxial cable 20 from the front end side of the power coaxial cable 20. Since the gap between the inner surface of the large-diameter portion 812 and the outer semiconductive layer 21d for internal insulation is smaller than the gap between the inner surface on the rear end side of the outer conductor fixing bracket 331 and the outer semiconductive layer 21d for internal insulation, In the state of being inserted into the coaxial cable 20, the direct-out jig 81 shown in FIG. 6 has almost no backlash compared to the backlash of the outer conductor fixing metal fitting 331 alone in the state as shown in FIG. The direct jig 81 is inserted into the outer conductor fixing bracket 331 and the large diameter portion 812 is engaged with the stepped portion 3312 in the outer conductor fixing bracket 331. As a result, the outer conductor fixing metal fitting 331 is also free from backlash.

  In this state, the outer conductor 22a is lightly struck on the outer conductor fixing bracket 331 with a hammer such as a resin hammer, and the outer conductor 22a opened to the outside is laid along the outer conductor fixing bracket 331. Specifically, the outer conductor 22a may be provided with a ridge in the shape of the outer conductor 22a such that the outer conductor 22a is laid along the outer surface of the hollow truncated cone portion 3311 of the outer conductor fixing bracket 331. In this embodiment, since the outer conductor 22a is inserted into the outer conductor 22a after the outer conductor 22a is bent by the root bending hook process, the outer conductor 22a is bent. This facilitates the step of disposing the outer conductor fixing ring 332 in the subsequent process on the outer conductor 22a disposed on the inclined surface of the outer conductor fixing bracket 331, so that it follows the shape of the outer conductor fixing bracket as in the prior art. Thus, it is not necessary to hit the external conductor 22a strongly with a hammer or other striking tool on the external conductor fixing bracket so that the shape of the external conductor 22a is deformed. Tap lightly enough to lie along. For this reason, there is no fear of metal powder such as copper powder due to contact between metals as in the prior art, and the external conductor fixing metal fitting 331 is connected to the power coaxial cable 20 (in this embodiment, external for internal insulation). There is no risk of worrying about colliding with the semiconductive layer 21d) and damaging it. Even if the impact when the external conductor 22a is tapped is transmitted to the external conductor fixing bracket 331, the external conductor fixing bracket 331 is in contact with the directing jig 81, so The external insulating semiconductive layer 21d is not brought into contact with the internal insulating external semiconductive layer 21d with such an impact that the external external semiconductive layer 21d is damaged.

  Next, the outer conductor fixing ring 332 previously inserted in the power coaxial cable 20 is moved and positioned on the outer conductor 22 a disposed on the inclined surface of the outer conductor fixing bracket 331. At this time, the position of the bolt hole of the outer conductor fixing ring 332 and the position of the bolt hole of the outer conductor fixing metal fitting 331 are made to correspond to each other at a position overlapping in the axial direction.

  The outer conductor fixing metal fitting 331 is inserted to a position away from the tip of the power coaxial cable 20 by a predetermined length D. This predetermined length D is a length necessary for being accommodated in the coaxial cable terminal receiving portion 13a via the first electric field relaxation component 32 (see also FIG. 3).

  Next, as shown in FIG. 7, the outer conductor 22 a is sandwiched between the outer conductor fixing bracket 331 and the outer conductor fixing ring 332 by using a tightening jig 90.

  Here, the fastening jig 90 will be described. FIG. 8 is an exploded view of the fastening jig shown in FIG.

  The tightening jig 90 is sandwiched between the outer conductor fixing ring 332 and the outer conductor fixing bracket 331 from both sides in the longitudinal direction of the power coaxial cable 20 and fixed with a specified torque (see FIG. 7). .

  The tightening jig 90 includes a first flange portion 92 and a second flange portion 94 that are disposed so as to cover the outer conductor 22a exposed from the distal end portion 20a of the power coaxial cable 20 from the outer peripheral side, and the first flange portion 92. And a torque applying portion 96 that is stretched over the second flange portion 94.

  The first flange portion 92 presses the outer conductor fixing ring 332 from the rear end side to the front end side of the power coaxial cable 20. In the present embodiment, the first flange portion 92 is formed in a metal disk shape, and has an opening 922 having an inner diameter larger than the outer diameter of the outer conductor 22a, and an outer conductor fixing ring 332. A pressing surface 924 that contacts the rear end surface and presses the outer conductor fixing ring 332 toward the front end side, and a torque applying portion mounting portion 926. The opening 922 communicates with the notch 929.

  The first flange portion 92 has a notch portion at a position on the rear end side of the outer conductor fixing ring 332 after setting a second flange portion 94 to be described later at the distal end portion 20a (see FIG. 7) of the power coaxial cable 20. The power coaxial cable 20 is disposed in the opening 922 through the through hole 922.

  The first flange portion 92 has a main body portion 928 with an opening 922 formed at the center, and the main body portion 928 has a notch 929 that communicates with the opening 922. A surface (tip surface) on the outer conductor fixing ring 332 side of the main body portion 928 forms a pressing surface 924, and a bolt hole as a torque applying portion attaching portion 926 is formed in the main body portion 928.

  The main body 928 may be formed in any manner as long as it has a configuration including the opening 922, the pressing surface 924, the torque applying portion mounting portion 926, and the notch 929, but in the present embodiment, the main body 928 has a plate shape. There is a disk shape with a notch 929.

  The opening 922 does not contact the outer conductor 22a on the hollow truncated cone portion 3311 of the outer conductor fixing bracket 321 when the first flange portion 92 is fixed to the second flange portion 94 described later by the torque applying portion 96. The outer conductor fixing ring 332 has a larger diameter than the inner diameter of the outer conductor fixing ring 332 and communicates with the notch (see FIGS. 7 and 8).

  A plurality of bolt holes as the torque applying portion attaching portion 926 are formed outside the opening portion 922 in the main body portion 928. It is desirable that the bolt hole is disposed at a symmetrical position with respect to the center of the first flange portion 92. In the present embodiment, three bolt holes 926 are formed in the main body 928 outside the opening 922, and the shape connecting the centers of the bolt holes 926 is a triangle (preferably a regular triangle). Is formed.

  The second flange portion 94 presses the outer conductor fixing metal fitting 331 from the front end to the rear end side of the power coaxial cable 20 (see FIG. 7). In the present embodiment, the second flange portion 94 is formed in a disk shape made of metal and has an opening portion 942 having an inner diameter larger than the outer diameter of the outer semiconductive layer 21d for internal insulation, A pressing surface 944 that contacts the front end surface of the outer conductor fixing metal fitting 331 and presses the outer conductor fixing metal fitting 331 to the rear end side, and a torque applying portion attaching portion 946 are provided.

  The second flange portion 94 is disposed closer to the distal end side of the power coaxial cable 20 than the outer conductor fixing bracket 331 through the power coaxial cable 20 through the opening 942.

  The second flange portion 94 has a main body portion 948 having an opening 942 formed in the center, and the surface of the main body portion 948 on the outer conductor fixing metal fitting 331 side (rear end side surface) forms a pressing surface 944. Bolt holes are formed in the main body portion 928 as the torque applying portion attaching portion 946.

  The main body portion 948 may be formed in any manner as long as it has an opening 942, a pressing surface 944, and a torque applying portion attaching portion 946. However, in the present embodiment, the main body portion 948 has a plate shape and a disc shape. Is formed.

  As shown in FIG. 7, the pressing surface 944 engages with the front end surface of the outer conductor fixing metal fitting 331 (the front end surface of the flange portion 3313). In the opening 942, an external insulating external semiconductive layer 21d stripped at the tip 20a of the power coaxial cable 20 is disposed. The opening 942 is larger than the outer diameter of the direct lead jig 81 on the outer semiconductive layer 21 d for outer insulation and smaller than the outer diameter of the outer conductor fixing metal fitting 331.

  In this embodiment, the opening 942 has a smaller inner diameter than the opening 922.

  A plurality of bolt holes as the torque applying portion attaching portion 946 are formed in the main body portion 948 so as to surround the opening portion 942. It is desirable that the bolt hole is disposed at a symmetrical position with respect to the center of the second flange portion 94. In the present embodiment, three bolt holes 946 are formed in the main body 948 outside the opening 942, and the shape connecting the centers of the bolt holes 926 is a triangle (preferably a regular triangle). Is formed.

  The torque applying portion 96 applies torque in a direction in which the outer conductor fixing ring 332 and the outer conductor fixing bracket 331 sandwiched between the first flange portion 92 and the second flange portion 94 approach each other, whereby the outer conductor fixing bracket 331 and the outer conductor fixing bracket 331 are externally connected. The outer conductor 22a is sandwiched and fixed by the conductor fixing ring 332.

  In the present embodiment, the torque application unit 96 includes a bolt (clamping bolt) 962 and a nut 961. The shaft portion of the bolt 962 is inserted into both the first flange portion 92 and the second flange portion 94 that are arranged to face each other, the head portion of the bolt 962 is locked to the second flange portion 94, and the first flange portion 92 is A nut 961 is screwed from the shaft end of the bolt to be inserted. In addition, the direction of the bolt 962 may be changed, the head of the bolt 962 may be locked to the first flange portion 92, and the nut 961 may be screwed into the shaft portion of the bolt 962 that passes through the second flange portion 94. .

  By tightening the bolt 962 and the nut 961 and applying torque, the first flange portion 92 and the second flange portion 94 are moved in a direction approaching each other, and the outer conductor fixing ring 332 and the outer conductor fixing bracket 331 are moved. The outer conductor 22a is sandwiched and fixed. In the present embodiment, the bolt holes of the first flange portion 92 and the second flange portion 94 are insertion holes through which the shaft portions of the bolts 962 are inserted, but the male screw of the bolt 962 is formed on the inner peripheral surface of the bolt holes. It is good also as a structure which forms the internal thread part screwed together to a part, and screws and fastens the volt | bolt 962 without using a nut.

  The fastening jig 90 configured in this way is attached to the external conductor connecting component 33. Specifically, the second flange portion 94 is passed from the distal end side of the power coaxial cable 20 and is brought into contact with the external conductor fixing metal fitting 331 on the external insulating outer semiconductive layer 21d of the distal end portion 20a.

  Next, in a state where the bolt 962 that is the torque applying portion 96 is inserted into the bolt hole that is the torque applying portion attaching portion 946 of the second flange portion 94, the first flange portion 92 is connected to the rear end side of the outer conductor fixing ring 332. At the position, the power coaxial cable 20 is disposed in the opening 922 through the notch, and the bolt 962 is inserted into the bolt hole which is the torque applying portion attachment portion 926 of the first flange portion 92, and the nut 961. Is screwed onto the bolt 962. Here, the width of the fastening jig 90, that is, the length between the first flange portion 92 and the second flange portion 94 is set to a predetermined value. This predetermined value corresponds to the length of the external conductor fixing bracket 331 and the outer conductor fixing ring 332 when the outer conductor 22a is temporarily fixed by sandwiching the outer conductor fixing bracket 331 and the outer conductor fixing ring 332. Length value. Thus, the fastening jig 90 is set with the external conductor 22a temporarily fixed.

  Then, by tightening the bolts 962 (three in this embodiment) of the torque applying portion 96 with a predetermined torque, a prescribed torque is applied to the outer conductor 22a between the outer conductor fixing bracket 331 and the outer conductor fixing ring 332. Give. Specifically, the bolt 962 is tightened with a predetermined torque using a torque wrench or the like while holding the nut 961 with a monkey wrench or the like so that the nut 961 does not rotate. Here, since the three bolts 962 are arranged, the torque is equally applied by tightening with the same torque so as not to be tightened. Here, the overall specified torque applied to the outer conductor 22a between the outer conductor fixing bracket 331 and the outer conductor fixing ring 332 after the bolt 962 has been tightened with a predetermined torque is the outer conductor fixing bracket 331 described later. When tightening the outer conductor fixing ring 332 with the bolt V2, the overall specified torque applied to the outer conductor 22a between the outer conductor fixing metal fitting 331 and the outer conductor fixing ring 332 is equal to the torque of the same axial force. A predetermined torque when the bolt 962 is tightened is set.

  Next, the fastening jig 90 is removed from the front end portion 20a of the power coaxial cable 20, and the bolt V2 for fixing the outer conductor is inserted into the outer conductor fixing ring 332 from the rear end side of the power coaxial cable to fix the outer conductor. The metal fitting 331 is screwed and tightened (see FIG. 3). At this time, the bolts V2 that are evenly arranged with respect to the center tighten the bolts V2 uniformly with a predetermined torque so as not to be tightened. Here, the predetermined torque when the bolt V2 is tightened is the total specified torque applied to the outer conductor 22a between the outer conductor fixing bracket 331 and the outer conductor fixing ring 332 when tightening with the predetermined torque. The overall specified torque applied to the outer conductor 22a by the jig 90 is set to be the same axial torque. The predetermined torque when the bolt 962 is tightened does not necessarily match the predetermined torque when the bolt V2 is tightened, and these predetermined torques are appropriately selected depending on the size and number of the bolts 962 and V2. As a result, the outer conductor 22 a sandwiched between the outer conductor fixing ring 332 and the outer conductor fixing bracket 331 is evenly pressed and fixed between the outer conductor fixing bracket 331 and the outer conductor fixing ring 332. At this time, it is confirmed that the outer conductor fixing metal fitting 332 is located at a position away from the tip of the power coaxial cable 20 by a predetermined length D.

  After fixing the outer conductor 22a in this way, the direct-out jig 81 is removed, and the wire rod (here, annealed copper wire) (not shown) that temporarily holds the outer conductor 22a together is removed.

  Next, the power coaxial cable 20 is inserted into the first electric field relaxation component 32 from the front end side of the power coaxial cable 20. In that case, each part and the predetermined position (position shown in FIG. 3) which arrange | positions each part are wiped away with a solvent etc.

  Specifically, the compression device CU1 (the pressing metal pipe 324, the spring 323, and the pressing metal 322) of the electric field relaxation component 32 is inserted into the power coaxial cable 20, and then the first stress cone 321 is connected to the power coaxial cable. 20 is inserted.

  The first stress cone 321 is disposed on the outer peripheral surface of a portion extending from the inner insulator 21c to the inner insulating outer semiconductive layer 21d.

After the stopper 39 is inserted into the power coaxial cable 20, the adapter 38 is attached to the outer periphery of the conductor connection sleeve 31. A conductor contact such as a multi-ram band is attached to the outer periphery of the conductor connection sleeve 31 on the tip side from the recessed groove before the adapter 38 is attached. The adapter 38 is a component for filling the gap between the conductor insertion portion 11a of the conductor lead bar 11 and the outer periphery of the conductor connection sleeve 31 to make it electrically.
Thus, the front-end | tip part of the coaxial cable 20 for electric power with which each part was attached is inserted in the coaxial cable terminal receiving part 13a in the insulation part 13 of the insulation unit 10, considering the allowable bending radius of a cable.

  In the step of inserting the power coaxial cable 20, silicone oil is uniformly applied to each of the inner surface of the coaxial cable terminal receiving portion 13 a and the surface of the first stress cone 321 immediately before inserting the power coaxial cable 20.

  Next, the metal fitting pipe 324 is attached, and the first stress cone 321 is pressed against the coaxial cable terminal receiving portion 13a and fixed by the compression device CU1.

  Next, the inner surface of the end portion 13d of the insulating portion 13 and the surface of the second stress cone 341 are wiped with a solvent, and each portion of the second electric field relaxation component 34 is attached to each predetermined part (see FIG. 3). The second electric field relaxation component 34 is attached by fixing the pressing metal flange 342 to the end surface of the end portion 13d of the insulating portion 13 with the bolt V3, thereby stopping the second stress cone 341 with the pressing metal flange 342. The second stress cone 32 is brought into close contact with the inner surface of the end portion 13 d of the insulating portion 13 by pressing toward the 35 side. In this manner, the second electric field relaxation component 34 is attached to the insulating unit 10 while being positioned at a predetermined position (position shown in FIG. 3).

  Next, an end turn processing for filling the gap with the protective metal fitting 61 on the cable sheath 25, connection of the cable shielding layer 23 to the pressing metal flange 342, the protective metal fitting 61 at the rear end face of the second electric field relaxation component 34, that is, In the present embodiment, it is attached to the rear end face of the pressing metal flange 342, and steps such as fixing of the power coaxial cable 20 using a cleat are sequentially performed to assemble the end connection portion of the power coaxial cable.

  Note that the connection method of the power single-core cable 40 is a known connection method, and a description thereof will be omitted.

  According to the present embodiment, when the outer conductor 22a is fixed by being sandwiched between the outer conductor fixing bracket 331 and the outer conductor fixing ring 332, the outer conductor fixing bracket 331 that sandwiches the outer conductor 22a with the tightening jig 90. And the outer conductor fixing ring 332 are pressed. Specifically, the outer conductor 22a is peeled off at the front end of the power coaxial cable 20 so that the front end of the exposed outer conductor 22a is expanded, and then the outer conductor is fixed on the outer periphery of the front end of the power coaxial cable 20. The outer conductor 22 a is positioned between the metal fitting 331 and the outer conductor fixing ring 332. Next, the torque spanned between the first flange portion 92 and the second flange portion 94 with the outer conductor fixing ring 332 and the outer conductor fixing bracket 331 being sandwiched between the first flange portion 92 and the second flange portion 94 of the fastening jig 90. The bolt 962 that is the applying portion 96 is tightened with a predetermined torque. At this time, the first flange portion 92 presses the surface of the outer conductor fixing ring 332 opposite to the outer conductor fixing metal fitting 331 (the rear end surface of the outer conductor fixing ring 332), and the second flange portion 94 fixes the outer conductor. The surface of the metal fitting 331 opposite to the outer conductor fixing ring 332 (the end surface of the external conductor fixing metal fitting 331) is pressed. In this state, the overall specified torque applied to the outer conductor 22a between the outer conductor fixing bracket 331 and the outer conductor fixing ring 332 is that the bolt V2 is fixed to the outer conductor fixing bracket 331 and the outer conductor fixing ring 332 with a predetermined torque. When tightening, the overall specified torque applied to the outer conductor 22a between the outer conductor fixing metal fitting 331 and the outer conductor fixing ring 332 is the same axial torque. As a result, the outer conductor 22a is deformed along the shape of the outer conductor fixing bracket 331, and is deformed into a shape with a ridge along the outer conductor fixing bracket 331. That is, a shape when the outer conductor 22a is fixed between the outer conductor fixing bracket 331 and the outer conductor fixing ring 332, and a fixing shape of the outer conductor 22a are formed.

  As described above, according to the method of assembling the terminal connecting portion of the power coaxial cable according to the present embodiment, at least the inner conductor 21a, the inner insulator 21c, the outer conductor 22a, the outer insulator 22c, and the cable shield are sequentially arranged from the center. The front end portion 20a of the power coaxial cable 20 in which the layer 23 is formed concentrically is stripped to expose at least the inner conductor 21a, the inner insulator 21c, and the outer conductor 22a. Next, the outer conductor connecting component 33 electrically connected to the outer conductor 22a, the first electric field relaxation component 32 for controlling the electric field between the inner conductor 21a and the outer conductor 22a, and the outer conductor 22a and the cable shielding layer A cable terminal portion is formed by attaching a second electric field relaxation component 34 for controlling the electric field between the two. Next, the cable terminal portion surrounds the outer peripheral surface of the conductor extraction rod (inner conductor connection portion) 11 electrically connected to the inner conductor 21 a and the embedded electrode 12 electrically connected to the outer conductor connection component 33. In this way, the coaxial cable terminal receiving portion 13a of the insulating portion 13 made of a hard insulating material is mounted and assembled. The outer conductor connecting component 33 includes an outer conductor fixing bracket (first fixing member) 331 and an outer conductor fixing ring (first fixing member) that clamps and fixes the outer conductor 22a with a specified torque via a bolt (fixing bolt) V2. Second fixing member) 332. A bending rod jig 71 is inserted into the inner base of the outer conductor 22a, a bending rod is attached so that the outer conductor 22a expands radially at the root portion, the bending rod jig 71 is removed from the power coaxial cable 20, and then the bolt Before the outer conductor 22a is clamped and fixed between the outer conductor fixing bracket (first fixing member) 331 and the outer conductor fixing ring (second fixing member) 332 by the (fixing bolt) V2, a fastening jig 90, an outer conductor fixing bracket (first fixing member) 331 and an outer conductor fixing ring (second fixing member) 332 arranged so as to sandwich the outer conductor 22a via the clamping bolt 962 of the clamping jig 90, A fixed shape in which the outer conductor 22a is fixed by an outer conductor fixing bracket (first fixing member) 331 and an outer conductor fixing ring (second fixing member) 332 by applying a torque equivalent to the specified torque. Comprising the step of.

  As a result, the outer conductor fixing bracket 331 and the outer conductor fixing ring 332 are positioned on the power coaxial cable 20 so as to press the outer conductor 22a evenly, so that the fastening jig 90 is fixed to the outer conductor fixing bracket 331 and the outer conductor. After removal from the fixing ring 332, the outer conductor fixing ring 332 and the outer conductor fixing bolt V2 spanned between the outer conductor fixing metal fittings 331 can be easily tightened with a predetermined torque.

  Further, since the outer conductor fixing bracket (first fixing member) 331 is inserted into the outer conductor 22a after the outer conductor 22a is bent with the bending hook jig 71, the outer conductor fixing in the subsequent process is performed. Since the process of arranging the ring 332 on the outer conductor 22a arranged on the inclined surface of the outer conductor fixing metal fitting 331 has become easy, unlike the conventional case, the outer conductor 22a is deformed to follow the shape of the outer conductor fixing metal fitting 331. Therefore, it is not necessary to perform a strong hitting operation with a resin hammer from above the outer conductor 22a. Therefore, the power coaxial cable 20 at the position where the outer conductor fixing bracket 331 is disposed. In the present embodiment, the outer conductor fixing bracket 331 collides with the inner semiconductive outer semiconductive layer 21d and the power coaxial cable 20 is recessed. Thus, it is possible to prevent the insulation performance from deteriorating. Further, since the direct lead jig 81 is inserted inside the outer conductor fixing bracket 331 until the fixing of the outer conductor 22a is completed, the outer conductor fixing bracket 331 is accurately fixed without being inclined. . Further, before the outer conductor 22a on the outer conductor fixing bracket 331 is fixed, the outer conductor 22a opened outward is struck lightly with a striking tool to lie along the outer conductor fixing bracket 331. However, there is no risk of worrying that the outer conductor fixing metal fitting 331 collides with the power coaxial cable 20 (in this embodiment, the outer semiconductive layer for internal insulation 21d) and is damaged, such as a dent. Even if the impact when the external conductor 22a is tapped is transmitted to the external conductor fixing bracket 331, the external conductor fixing bracket 331 is in contact with the directing jig 81, so The external insulating semiconductive layer 21d is not brought into contact with the internal insulating external semiconductive layer 21d with such an impact that the external external semiconductive layer 21d is damaged.

  Since the outer conductor 22a can be easily fixed in this manner, the outer conductor 22a is pressed evenly around the circumference when the outer conductor 22a is sandwiched and fixed between the outer conductor fixing ring 332 and the outer conductor fixing bracket 331. The outer conductor fixing bracket 331 and the outer conductor fixing ring 332 are easily fixed.

  Since the outer conductor 22a is once clamped and crushed with the same force as the axial force of the bolt V2 when the outer conductor 22a is fixed using the tightening jig 90, the specified torque at the time of actual fixing using the bolt V2 Can be easily applied, and it is possible to reduce the extension of working time due to reassembly without applying torque to the bolt V2 many times, and to reduce the influence on the mechanical properties of the bolt V2.

  By the way, when the outer conductor fixing bracket 331 and the outer conductor fixing ring 332 are tightened with a specified torque by the tightening jig 90, a large axial force is applied to the outer conductor fixing bracket 331.

  As a result, when the bolts cannot be tightened evenly in the tightening jig 90, torque is not evenly applied to the bolts, and a slight distortion may occur on the surface on the front end side of the external conductor fixing bracket 331.

The outer conductor fixing metal fitting 331 has a structure that contacts the inner surface of the inserted metal fitting pipe 324 by a conductor contactor 37 such as a multi-ram band disposed around the outer metal fixing metal fitting 331 (see FIG. 3).
For this reason, in the terminal connection part 1 of this Embodiment, it replaces with the external conductor fixing metal fitting 331, and is the case where the conventional external conductor 331A which is a structure without the chamfering part 3315 in the structure of the external conductor fixing metal fitting 331 is used. It is considered that a slight distortion occurs on the tip side surface (see FIG. 9), and the external conductor fixing metal fitting 331 fitted with the conductor contactor 37 cannot be inserted into the pressing metal pipe 324 due to this distortion and cannot be fitted. It is done. The outer conductor fixing bracket 331A has a hollow truncated cone portion 3311A similar to the hollow truncated cone portion 3311 of the outer conductor fixing bracket 331 and a flange portion 3313A that is not chamfered.

  However, in the terminal connection portion 1 of the power coaxial cable assembled by applying this embodiment, a chamfered portion 3315 is formed on the outer peripheral edge on the distal end side of the outer conductor fixing metal fitting 331 (in FIG. 4). A chamfered portion 3315 indicated by a broken line).

  Thereby, even if the surface of the front end side of the external conductor fixing metal fitting 331 is distorted by tightening the bolt 962 by the tightening jig 90, as shown by the solid line of the chamfered portion 3315 in FIG. The inner diameter of the pipe 324 (in this embodiment, the outer peripheral surface of the flange portion 3313 on which the multi-ram band is formed) does not become larger in the radial direction, and can be suitably fitted to the pressing metal pipe 324.

  Further, for example, in the embodiment, the case where the tip end portion 11b of the conductor lead bar 11 is applied to a gas termination connection portion connected to a power device has been described. The present invention can also be applied to a middle terminal connection or an intermediate connection.

  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.

DESCRIPTION OF SYMBOLS 1 Terminal connection part of power coaxial cable 10 Insulation unit 11 Conductor extraction rod 12 Embedded electrode 13 Insulation part 13a Coaxial cable terminal receiving part 14 Shielding layer 15 Mounting flange 20 Power coaxial cable 20a Tip part 21a Inner conductor 21c Inner insulator 21d External semiconductive layer 22a for internal insulation External conductor 22c External insulator 22d External semiconductive layer 23 for external insulation Cable shielding layer 25 Cable sheath 31 Conductor connection sleeve 32 First electric field relaxation component 321 First stress cone CU1 First Compression device 322 Press fitting 323 Spring 324 Press fitting pipe 33 External conductor connecting component 331 External conductor fixing fitting 332 External conductor fixing ring 34 Second electric field relaxation component 341 Second stress cone CU2 Second compression device 342 Press fitting flange 35, 39 Stopper 4 Power single-core cable 50 connecting parts 51 stress cone 52 compressor 53 cable protection bracket 71 curl jig 81 straight out the jig 90 fastening jig 92 first flange 94 second flange portion 96 torque applying unit

Claims (5)

In order from the center, at least the inner conductor, the inner insulator, the outer conductor, the outer insulator, and the end portion of the power coaxial cable in which the cable shielding layer is formed concentrically, step at least the inner conductor, An inner insulator, an outer conductor connecting component that exposes the outer conductor and is electrically connected to the outer conductor, a first electric field relaxation component for controlling an electric field between the inner conductor and the outer conductor, and Attaching a second electric field relaxation component for controlling the electric field between the outer conductor and the cable shielding layer to form a cable terminal portion;
The cable terminal portion is formed so as to surround an outer peripheral surface of an embedded electrode electrically connected to the inner conductor connecting portion and the outer conductor connecting component electrically connected to the inner conductor, and is rigid. In the method of assembling the terminal connection portion of the power coaxial cable to be mounted and assembled to the coaxial cable terminal receiving portion of the insulating portion made of the insulating material,
The outer conductor connecting component has a first fixing member and a second fixing member that are clamped and fixed in a state where the outer conductor is pressed with a specified torque via a fixing bolt,
Inserting a bending rod jig at the inner base of the outer conductor, attaching a bending rod that expands the outer conductor in the radial direction at the root portion, and removing the bending rod jig from the power coaxial cable ;
By applying a torque equivalent to the specified torque to the first fixing member and the second fixing member arranged so as to sandwich the outer conductor via the tightening bolt of the tightening jig, Forming the outer conductor into a fixed shape fixed by the first fixing member and the second fixing member ;
Removing the tightening jig from the power coaxial cable, and fixing the outer conductor between the first fixing member and the second fixing member with the fixing bolt .
Assembling method of terminal connection part of coaxial cable for electric power. The fastening jig includes a first flange portion that presses a surface of the second fixing member opposite to the first fixing member;
A second flange portion that presses a surface of the first fixing member opposite to the second fixing member;
The step of forming the outer conductor in the fixed shape includes connecting the plurality of tightening bolts so as to span the first flange portion and the second flange portion, and tightening the tightening bolt to Pressing the outer conductor sandwiched between the first fixing member and the second fixing member at the second flange portion;
The method for assembling a terminal connection portion of the power coaxial cable according to claim 1. The first fixing member is a hollow frustum shape whose outer surface is reduced in diameter toward the rear end side of the power coaxial cable, and is an external conductor fixing bracket having conductivity,
The second fixing member is an outer conductor fixing ring having an inner peripheral surface along a hollow frustoconical outer peripheral surface in the outer conductor fixing bracket,
The outer conductor fixing ring is disposed on the outer surface side of the outer conductor from the rear end side of the power coaxial cable, and on the inner surface side of the outer conductor, on the outer surface of the outer conductor fixing bracket from the front end side of the power coaxial cable. The outer conductor fixing bracket is disposed so that the outer conductor is positioned, and the outer conductor is positioned between the outer conductor fixing ring and the outer conductor fixing bracket,
At the front end side of the outer conductor fixing bracket, after arranging a cylindrical straight-out jig between the outer periphery of the power coaxial cable and the inner periphery of the outer conductor fixing bracket, the clamping bolt of the clamping jig Tighten,
The method for assembling a terminal connection portion of the power coaxial cable according to claim 1. The direct-out jig has a resin direct-out main body part, and a large-diameter part having an outer diameter larger than the direct-out main body part at one end of the direct-out jig,
The inner diameter of the large diameter portion is smaller than the inner diameter of the outer conductor fixing bracket,
The direct jig is engaged with a step portion on an inner periphery of the outer conductor fixing metal fitting;
The method for assembling a terminal connection portion of the power coaxial cable according to claim 3. The outer conductor fixing metal fitting is provided with a chamfered portion on an outer peripheral edge on the tip side.
The method for assembling a terminal connection portion of the power coaxial cable according to claim 3 or 4.

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