JP6089010B2 - Power cable connecting apparatus and power cable connecting method - Google Patents

Description

  The present invention relates to a power cable connecting device and a power cable connecting method.

2. Description of the Related Art Conventionally, as a connection portion of a power cable, a structure is known in which cable conductors that are exposed by stepping off ends of a power cable are connected to each other, and an insulating cylinder is attached to the conductor connection portion.
The conductor of the power cable is connected at the construction site, and the method of compressing the cylinder for connecting the power cable is most often used for this. For example, as shown in Patent Document 1, an insulating cylinder with a diameter-enlarged support cylinder is used in which a room-temperature-shrinkable insulating cylinder (molded product of silicone rubber or EP rubber) is expanded by a diameter-enlarged support cylinder. .
As the construction procedure, after inserting the power cable into the insulating cylinder with the expanded support cylinder and connecting the conductors of the power cables, the conductor connection part is arranged at the center of the insulated cylinder with the expanded support cylinder The insulating cylinder with the expanded diameter support cylinder is moved, and the expanded diameter support cylinder is removed, whereby the diameter of the insulated cylinder is reduced and tightly fixed to the outer periphery of the power cable including the conductor connecting portion.
After mounting the insulating cylinder as described above, an electrical shielding process using a metal layer, a protective tube assembly for enhancing mechanical strength, and a grounding wire drawing process from the protective tube were performed.

JP 2001-37065 A

However, the conventional technique has the following problems.
First, the insulation cylinder attached to the conductor connection part between the power cables has an inner diameter so that the power cable can be inserted into the hollow part of the insulation cylinder and moved along the power cable during assembly at the construction site. The diameter is expanded until approximately twice or more. The outer diameter changes approximately 1.5 times or more when the expanded diameter is maintained and when the reduced diameter is mounted.
For this reason, the electrical shielding process and the protective tube assembly can be performed only after the insulating cylinder is attached to the power cable, and it takes field construction time to perform these operations.
In addition, if construction is performed in the order of installation of the insulating cylinder, electrical shielding treatment, and protective tube assembly, a gap will inevitably remain between the electrical shielding layer and the inner surface of the protective tube. Since this gap greatly contributes to the temperature rise during power cable operation, it is preferable not to leave a gap. Therefore, the work of injecting a waterproof compound or the like into this gap after assembling the protective tube is also required.
When a series of operations from the installation of the above insulating cylinder to the injection of a waterproof compound or the like is performed at the construction site where the power cables are connected, there is a problem that the working time at the construction site becomes long.

As a method of shortening the connection construction time between power cables, there is a method of shipping after completing an electrical shielding process, a protective tube assembly and a compound injection process for an insulating cylinder at a factory. In the method of attaching to the cable after expanding the diameter by 2 times or more, the shield structure or the like formed at the factory buckles and does not perform its function.
In addition, if the diameter of the protective tube is increased while the waterproof compound is injected, there is a risk that the insulating cylinder cannot be expanded due to the repulsive force of the waterproof compound, or the compound or the protective tube may be damaged.
There is also a method of injecting the waterproofing compound in a state where the diameter of the insulating cylinder is expanded, but after attaching to the cable, a gap is generated between the protective tube and the waterproofing compound, which has the effect of mitigating the temperature rise. It will fade.
In order to solve these problems, at the connection construction site between power cables, the inner diameter is not expanded (pre-expansion) to the dimension that allows the power cable to be inserted into the insulating cylinder, and the connection ends of the two power cables are insulated. A method (slip-on method) in which the cylinders are inserted from the opposite sides to the middle of the cylinder body is adopted, and shipping is performed in a state where electrical shielding processing, protective tube assembly, and compound injection processing are completed at the factory.
However, in this method, there are the following problems when the connection end of the power cable is inserted into the insulating cylinder at the connection construction site between the power cables.
For one thing, when inserting the connecting end of the power cable into the insulating cylinder, if the operator grips and inserts the protective tube, the protective tube and the insulating cylinder will be displaced relative to each other, and installed in the proper mounting position. There is a problem that it cannot be done.
In addition, when electrical connection conductors such as female ends are installed in the insulation cylinder in advance in order to obtain electrical connection by the slip-on method, when inserting the connection end of the power cable into the insulation cylinder There is a problem that the electric connection conductor is pushed in, and a relative displacement between the electric connection conductor and the insulating cylinder is caused.
Furthermore, due to the surface pressure between the insulating cylinder and the power cable, there is a problem that excessive friction occurs at the time of insertion, which makes it difficult to insert by human power.

The present invention has been made in view of the above-described problems in the prior art, and can improve the workability at the connection construction site between power cables and improve the productivity and reliability of the power cable connection portion. It is an object of the present invention to provide a power cable connection device and a power cable connection method that can be used.

The invention according to claim 1 for solving the above-described problems is an insulating cylinder attached to a conductor connecting portion connecting conductors of a power cable;
An electrical shielding layer applied to the outer peripheral side of the insulating cylinder;
A protective tube provided on the outer peripheral side of the electrical shielding layer,
The insulating cylinder receives a connection end of one power cable inserted from one end opening of a hollow portion of the insulating cylinder, and receives a connection end of another power cable inserted from the other end opening. The conductors of the one power cable and the other power cable are configured to be connectable in the hollow portion,
An insertion jig is attached, and a distal end portion of the insertion jig is inserted into a receiving portion that receives the connection end portion formed in the hollow portion of the insulating cylinder,
In order to insert the connection end portion into the receiving portion when the power cable is connected, the rear end portion of the insertion jig extending from the receiving portion functions as a gripping portion, and the insertion jig is It is the electric power cable connection apparatus hold | maintained so that extraction from a receiving part is possible.

Invention of Claim 2 has two connection parts, the electrical connection conductor which connects the conductors of an electric power cable is installed in the hollow part of the said insulation cylinder, and one connection part of the said electrical connection conductor is the following. It is connectable with a connection terminal attached to the conductor tip of the connection end of the one power cable, and is arranged toward one end opening of the hollow portion of the insulating cylinder, and the other connection is The power cable connection device according to claim 1, wherein the power cable connection device can be connected to a connection terminal attached to a conductor tip of a connection end of the power cable and is arranged toward the other end opening of the hollow portion of the insulating cylinder. is there.

  According to a third aspect of the present invention, the insertion jig is a restricting portion for restricting the insulating cylinder from approaching a rear end of the insertion jig at a portion outside the inner diameter range of the insulating cylinder. The power cable connecting device according to claim 1 or 2, wherein

  According to a fourth aspect of the present invention, the insertion jig is a tapered pipe in which at least the outer diameter of the tip portion decreases along the insertion direction. This is a power cable connecting device.

  The invention according to claim 5 is such that the connection end can be inserted into the receiving portion by inserting the connection end of the power cable into the pipe inserted into the receiving portion, and the connection end is The power cable connecting device according to claim 4, wherein the pipe can be removed from the receiving portion while being inserted into the receiving portion and the pipe.

  A sixth aspect of the present invention is the power cable connecting device according to any one of the first to third aspects, wherein the insertion jig is a spiral core.

  The invention according to claim 7 is capable of inserting the connection end portion into the receiving portion by inserting the connection end portion of the power cable into the spiral core inserted into the receiving portion, and the connection end portion. The power cable connecting device according to claim 6, wherein the spiral core can be removed from the receiving portion in a state where the spiral core is inserted into the receiving portion and the spiral core.

  The invention according to claim 8 is the power cable connecting device according to any one of claims 1 to 7, wherein a buffer material is installed between the electrical shielding layer and the protective tube.

  A ninth aspect of the present invention is the power cable connecting device according to any one of the first to eighth aspects, wherein an anticorrosive layer is provided on an outer peripheral side of the protective tube.

The invention according to claim 10 is an insulating cylinder attached to a conductor connecting portion connecting conductors of a power cable,
An electrical shielding layer applied to the outer peripheral side of the insulating cylinder;
A protective tube provided on the outer peripheral side of the electrical shielding layer,
Insertion jig is attached, by using the insertion jig power cable connecting apparatus tip is inserted into accommodate receiving unit receives the connection end portion that will be formed in the hollow portion of the insulating cylinder of the power cables A power cable connection method for connecting each other,
After the electrical shielding layer and the protective tube are applied to the insulating cylinder and the insertion jig is inserted,
While holding the rear end portion extending from the receiving portion of the insertion jig to the outside, the connection end portion of one power cable is inserted from one end opening of the hollow portion of the insulating cylinder, and the other end opening is inserted. Inserting the connection end of the power cable and connecting the conductors of the one power cable and the other power cable within the hollow portion of the insulating cylinder, and
And a step of removing the insertion jig from the receiving portion.

According to the present invention, since an electrical shielding layer, a protective tube, etc. are already provided for the insulating cylinders before the connection between the power cables, these parts can be produced in the factory, and therefore the connection construction between the power cables is performed. It is possible to reduce the amount of work and time on site.
Moreover, productivity improvement, quality improvement, and uniformity can be achieved by factory production.
Furthermore, since the operator can grip the rear end of the insertion jig at the connection construction site between the power cables, the workability of inserting the connection end of the power cable is improved, and the protective tube, the insulating cylinder, and the electrical connection The relative deviation between the conductor and the insulating cylinder can be suppressed.
Through the above-mentioned factory production and work at the connection construction site between the power cables, the productivity and reliability of the power cable connecting portion can be improved.

It is an axial sectional view of a power cable connection part in a 1st embodiment of the present invention. It is an axial sectional view of the power cable connecting device concerning a 1st embodiment of the present invention. It is the figure which showed the part by which the insulation cylinder and the protection tube of the power cable connecting device which concern on 1st Embodiment of this invention are arrange | positioned with a frame. FIG. 4 shows an outline of a structure in which a protective tube having an inner flange structure at both ends is applied to a portion corresponding to the inside of the frame shown in FIG. 3. It is a side view of the site | part containing the connection edge part of an electric power cable. The state which provided the slip-on connection terminal with respect to the structure shown in FIG. 5 is shown. It is an axial sectional view of a power cable connecting device according to a second embodiment of the present invention. It is an axial sectional view of a power cable connecting device according to a third embodiment of the present invention.

  An embodiment of the present invention will be described below with reference to the drawings. The following is one embodiment of the present invention and does not limit the present invention.

[First Embodiment]
FIG. 1 shows an axial cross-sectional view of the power cable connecting portion in the first embodiment of the present invention. Moreover, the axial sectional view of the power cable connecting device according to the first embodiment of the present invention is shown in FIG. That is, FIG. 1 shows a completed form of a power cable connecting portion at a connection construction site between power cables, and FIG. 2 shows a form of the power cable connecting apparatus 1 produced in a factory. The power cable connecting device 1 shown in FIG. 2 is supplied to and applied to the connection construction site, whereby the power cable connecting portion shown in FIG. 1 is configured.
As shown in FIG. 1, the power cables 30 and 30 are connected to each other.

(1) First, I will explain along the production process in the factory.
(A) First, the rubber block insulating cylinder 10 is molded as in the prior art.
(B) Next, the electrical connection conductor 11 having female contact portions 11a, 11b for multi-contact at both ends is installed at the axial center portion in the hollow portion of the rubber block insulating cylinder 10. The electrical connection conductor 11 electrically connects the conductors of the power cables 30 and 30 inserted into the rubber block insulating cylinder 10.
(C) Next, on the outer peripheral side of the rubber block insulating cylinder 10, an electrical shielding layer 12 similar to that performed at a conventional construction site is applied. The electrical shield layer 12 is required to be connected with a current capacity equivalent to that of the electrical shield layer 31 of the power cable 30 (shield bond). Specifically, the electrical shield layer 31 of the power cable 30 Copper braided wires with the same cross-sectional area or more are applied. A crimp terminal 13 is attached to the end of the electrical shielding layer 12 so that it can be connected to the electrical shielding layer 31 of the power cable 30 in a short time at the construction site.

(D) Next, a buffer material 15 (compound, silicone gel, non-ferrous wool, etc.) is installed between the electrical shielding layer 12 and the protective tube 14 (14a, 14b). In the present embodiment, the entire protective tube 14 is configured by connecting a relatively long protective tube 14a and a relatively short protective tube 14b in the axial direction.
In the case of a buffer material that is liquid before curing, such as a compound or a silicone gel, the buffer material 15 is placed in the protective tube 14a after the rubber block insulating cylinder 10 is disposed, and then joined to the protective tube 14b. The buffer material 15 is injected from the gap on the side, and after the buffer material 15 is cured, the protective tube 14b is joined to the protective tube 14a and the lid is closed.
The compound may be butadiene rubber or the like conventionally used for filling the protective tube in the connection portion, and there is no special requirement for application to the present invention. Silicone gel is a silicone oil blended with a curing agent. “Soft and small load due to low crosslink density, easily deforms under pressure”, “Low elastic modulus to relieve stress due to thermal expansion”, “ Commercially available products (such as Shin-Etsu Silicone KE-1052A / B and Toray 3-4118Gel A & B) are available.
On the other hand, in the case of a deformable solid such as non-ferrous wool, the cushioning material 15 is wound around the rubber block insulating cylinder 10 provided with the electrical shielding layer 12 so that the outer diameter is slightly larger than the inner diameter of the protective tube 14a. By inserting the protective tube 14a into the protective tube 14a, sufficient adhesion can be ensured among the rubber block insulating cylinder 10 (electrical shielding layer 12), the buffer material 15, and the protective tube 14a.
Due to the deformation of the buffer material 15, it is possible to cope with slight fluctuations in the outer diameter of the rubber block insulating cylinder 10 generated during the construction of the power cable.

(E) The protective tube 14 is narrowed so that both ends in the longitudinal direction are close to the outer diameter of the power cable 30. The protective tube 14 is a two-part product (protective tube 14a and protective tube 14b), and the rubber block insulating cylinder 10 is formed by connecting the protective tube 14a and the protective tube 14b together with the installation of the buffer material 15 as described above. And the protective tube 14 are integrated.
The material of the protective tube 14 is a metal of aluminum or copper, and the protective tube 14 ensures the water shielding performance and the trauma resistant mechanical strength of the power cable connecting portion. When the cross-sectional area of the metal part of the protective tube 14 is sufficiently secured, the protective tube 14 can be substituted for this function by omitting the shielding bond by the electrical shielding layer 12.
The shape of the protective tube 14 is not a tapered shape (aperture shape) as shown in FIGS. 1 to 3 because the outer diameter of the central portion changes from a thick portion to the same diameter as the power cable 30 at the end. Further, the end portion can be made to have a structure close to a right angle by a flange structure or the like as shown in FIG. In this case, there are advantages that the entire length of the protective tube can be shortened and that the end portion of the rubber block insulating cylinder 10 can be easily visually confirmed during assembly at the power cable connection construction site. FIG. 4 shows an outline of the structure in which the protective tube 14F having both inner flange structures is applied to the portion corresponding to the inside of the frame A shown in FIG.

(F) After installing the electrical connection conductor 11, when installing the cushioning material 15 and assembling the protective tube 14, an insertion jig having an outer shape corresponding to the connection end 30a of the power cable 30 at the distal end 40a. As shown in FIG. 2, the tools 40 and 40 are inserted into the rubber block insulating cylinder 10, and the rubber block insulating cylinder 10 is corrected so as to be in the connection part assembly final form (shape dimension at the time of use).

(G) Further, the anticorrosion layers 16a and 16b are formed on the outer peripheral side of the protective tube. As shown in FIG. 2, the power cable connecting device 1 is shipped in a state where the insertion jigs 40 are inserted into the rubber block insulating cylinder 10.

(2) Next, description will be made while following the work process at the power cable connection construction site. (A) First, the connection end 30a of the power cable 30 is connected using a conventional rubber block insulating cylinder. The same processing as that of the unit is performed. Specifically, as shown in FIG. 5, each layer such as a conductor, an insulator, an external semiconductive layer, a shielding layer, a water shielding layer, and an anticorrosion layer is finished in a stepped shape from the power cable center layer side.

(B) Next, as shown in FIG. 6, the conductor 32 of the power cable 30 is inserted into a male slip-on connection terminal 33 having a multi-contact band, and is crimped (compression connection using a hydraulic die, etc.).
(C) Next, one side of the insertion jig 40 (here, the right side in FIG. 2) is pulled out and removed from the rubber block insulating cylinder 10 of the power cable connecting apparatus 1 assembled in the factory of FIG. The connection end 30a of the power cable 30 finished in (b) is inserted there.
At this time, the insertion jig 40 still inserted in the rubber block insulating cylinder 10 on the left side of FIG. 2 functions as a jig for insertion work. That is, the rear end portion 40b extending to the outside from the receiving portion 10a (opening m1 side) of the rubber block insulating cylinder 10 of the left insertion jig 40 in FIG. 2 functions as a gripping portion. The operator grasps the rear end portion 40b of the insertion jig 40 on the left side in FIG. 2 and firstly inserts the first receiving portion 10a (on the opening m2 side) in FIG. The connection end 30a of the power cable 30 is inserted.
A restricting portion 40c1 and a restricting portion 40c2 project from the outer peripheral surface of the portion of the insertion jig 40 that is not inserted into the rubber block insulating cylinder 10. When the first power cable 30 is inserted, the restricting portions 40c1 and 40c2 receive an external force that causes the rubber block insulating cylinder 10 to move the rubber block insulating cylinder 10 closer to the rear end portion 40b of the insertion jig 40. The rubber block insulating cylinder 10 is restricted from approaching the rear end portion 40b of the insertion jig 40. For this purpose, the restricting portions 40 c 1 and 40 c 2 are configured at a portion outside the inner diameter range of the rubber block insulating cylinder 10.
When the restricting portions 40c1 and 40c2 are in contact with the end surfaces of the rubber block insulating cylinder 10 and the protective tube 14, the relative positions in the axial direction of the electrical connecting conductor 11, the rubber block insulating cylinder 10 and the protective tube 14 are normal in design. Therefore, each part (10, 14, etc.) of the power cable connection device 1 can be mounted with high positional accuracy with respect to the conductor connection part between the power cables 30, 30.
Subsequently, the same operation is performed on the left side of FIG. 2 so that the power cables 30 are attached to both ends of the rubber block insulating cylinder 10 as shown in FIG. By this step, the slip-on connection terminal 33 that has been crimped to the tip of the conductor 32 of the power cable 30 and the electrical connection conductor 11 that has been installed at the center of the rubber block insulating cylinder contact with a predetermined size, A rated current can be passed between the conductor 32 of one power cable 30 and the conductor 32 of another power cable 30.

As described above, in the power cable connecting apparatus 1, the insulating cylinder 10 receives the connection end 30a of the one power cable 30 inserted from the one end opening m1 of the hollow portion of the insulating cylinder 10, and from the other end opening m2. The connection end 30a of the other power cable 30 to be inserted is received, and the conductors 32, 32 of the one power cable 30 and the other power cable 30 can be connected in the hollow portion of the insulating cylinder 10. It is a thing.
When the connection end 30a is inserted into the insulating cylinder 10, it is inserted with friction between the outer peripheral surface of the connection end 30a and the inner peripheral surface of the insulating cylinder 10, and the connection end 30a is caused by friction fitting. Is preferably fixed to the insulating cylinder 10.
Further, in the power cable connecting apparatus 1, one connecting portion 11 a of the electric connecting conductor 11 can be connected to the connecting terminal 33 attached to the conductor tip of the connecting end portion 30 a of the one power cable 30 and is an insulating cylinder. 10 is arranged toward one end opening m1 of the hollow portion, and the other connection portion 11b can be connected to the connection terminal 33 attached to the conductor tip of the connection end portion 30a of the other power cable 30 and is an insulating cylinder. It is arranged toward the other end opening m2 of the hollow portion of the body 10.
Further, the power cable connecting apparatus 1 is provided with an insertion jig 40 having an outer shape corresponding to the connection end portion 30a of the power cable 30 at the distal end portion 40a. The distal end portion 40 a of the insertion jig 40 has an outer shape corresponding to at least a portion inserted into the insulating cylinder 10 in the connection end portion 30 a of the power cable 30, and also has a portion corresponding to the slip-on connection terminal 33. It is preferable.
Moreover, the front-end | tip part 40a of the insertion jig 40 is inserted in the receiving part 10a which accepts the connection end part 30a formed in the hollow part of the insulation cylinder 10, and is connected to the receiving part 10a of the connection end part 30a at the time of power cable connection. The insertion jig 40 is held so as to be removable from the receiving portion 10a.

Also in the power cable connecting portion according to the present embodiment, the close contact between the insulator surface of the power cable 30 and the inner surface of the rubber block insulating cylinder 10 is one of technically important matters. This is a conventional rubber block insulating cylinder. Similar to the connecting portion using the rubber block insulating cylinder, the inner diameter of the rubber block insulating cylinder is made smaller than the outer diameter of the insulator of the power cable 30, whereby the adhesion effect due to the contraction force of the rubber block insulating cylinder 10 can be obtained.
The adhesion force (surface pressure) obtained at the interface is affected by the difference in diameter between the two, but in the present invention, the rubber block insulating cylinder 10 is made to prevent pre-expansion of the rubber block insulating cylinder 10. Since the phenomena such as permanent deformation and stress relaxation of the rubber material to be formed do not occur so much, there is an advantage that high adhesion can be obtained and maintained even if the difference in diameter between the two is reduced.

Here, the application example to a 66 kV class power cable is disclosed regarding the outer diameter of the rubber block insulation cylinder 10. FIG. Table 1 shows the time points at the time of molding the rubber block insulating cylinder 10 by the conventional pre-expansion method and the insertion method of the present invention (A), at the time of factory shipment (B), and after mounting on the power cable (C). The outer diameter at is posted. Two examples are shown for the present invention.
As shown in Table 1, the outer diameter of the rubber block insulating cylinder 10 at the time of molding (A) is common at Φ100 mm in the conventional pre-expansion method and the insertion method of the present invention.
As shown in Table 1, in the insertion method of the present invention, the amount of change in the outer diameter of the rubber block insulating cylinder 10 is small compared to the conventional pre-diameter method (particularly the difference between B and C in Table 1). It can be seen that the factory assembly shipment described in (1) above is possible.

(D) Now, after the power cable 30 is inserted into the rubber block insulating cylinder 10, the electrical shielding layer 12 and the electrical shielding layer 31 of the power cable 30 are connected by the crimp terminal 13.
(E) Finally, the end portion of the protective tube 14 and the anticorrosion layer 34 of the power cable 30 are connected by the heat-shrinkable tube 17 and the anticorrosion tape 18 to ensure water shielding performance and anticorrosion performance (the end of the power cable connection portion). Anticorrosion treatment). For this, the same technique as that of the conventional power cable connecting portion can be applied.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.
In the present embodiment, a taper pipe 140 shown in FIG. 7 is used as an insertion jig in the first embodiment. The power cable connecting apparatus 1A shown in FIG. 7 has a taper pipe 140 as an insertion jig, and the other configurations are the same as those in the first embodiment, and the factory production process and the power cables 30, 30 to be connected are the same. This is the same as in the first embodiment.

The tapered pipe 140 is a tapered pipe in which the outer diameter of at least a tip portion thereof decreases along the insertion direction.
In the first embodiment, the power cable 30 is inserted after removing the insertion jig. However, in this embodiment, the power cable 30 is inserted without removing the taper pipe 140, and the taper pipe is inserted after the power cable 30 is inserted. 140 is removed. That is, the connecting end 30a is inserted into the receiving portion 10a by inserting the connecting end 30a of the power cable 30 into the tapered pipe 140 inserted into the receiving portion 10a that receives the connecting end 30a of the rubber block insulating cylinder 10. In addition to being insertable, the tapered pipe 140 can be removed from the receiving portion 10a in a state where the connection end 30a is inserted into the receiving portion 10a and the tapered pipe 140.

As a work procedure at the connection construction site of the power cable, in the state where the taper pipe 140 is inserted into both ends of the rubber block insulating cylinder 10, the connection end portions of the two power cables 30 and 30 are inserted into the taper pipe 140. The connection between the power cables 30 and 30 is completed by inserting 30a and 30a, respectively, and projecting the conductor end portions of the connection end portions 30a and 30a from the taper pipe 140 and connecting them to the electrical connection conductor 11. At this time, the connection end 30a can be easily inserted without receiving pressure from the inner surface of the rubber block insulating cylinder 10. Moreover, since the electrical connection conductor 11 is pressed from both sides by the taper pipes 140 and 140, the electrical connection conductor 11 is not displaced. By making the inner diameter of the taper pipe 140 equal to or slightly larger than the outer diameter of the power cable 30, the cable insertion force can be greatly reduced. Such a reduction in insertion force can also solve the problem of causing the electrical connection conductor 11 to be displaced relative to the rubber block insulating cylinder 10.
When the insertion connection of the power cables 30 and 30 is completed, the taper pipe 140 is pulled out from the rubber block insulating cylinder 10, the diameter of the rubber block insulating cylinder 10 is reduced, and is firmly fixed to the connection end 30 a. The tapered pipe 140 can be easily pulled out of the rubber block insulating cylinder 10 by the tapered shape of the outer diameter of the tapered pipe 140.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG.
In the present embodiment, an insertion jig is a spiral core 240 shown in FIG. 8 with respect to the first embodiment. The power cable connecting apparatus 1B shown in FIG. 8 uses a spiral core 240 as an insertion jig, and the other configurations are the same as those in the first embodiment, and the factory production process and the power cables 30, 30 to be connected. This is the same as in the first embodiment.

  In the first embodiment, the power cable 30 is inserted after removing the insertion jig. However, in the present embodiment, the power cable 30 is inserted without removing the spiral core 240, and the power cable 30 is inserted before the spiral core is inserted. Pull 240 while solving. That is, the connecting end 30a is inserted into the receiving portion 10a by inserting the connecting end 30a of the power cable 30 into the spiral core 240 inserted into the receiving portion 10a that receives the connecting end 30a of the rubber block insulating cylinder 10. In addition to being insertable, the spiral core 240 can be removed from the receiving portion 10a in a state where the connection end portion 30a is inserted into the receiving portion 10a and the spiral core 240.

As a work procedure at the connection construction site of the power cable, the connection end portions of the two power cables 30 and 30 in the spiral core 240 in a state where the spiral core 240 is inserted at both ends of the rubber block insulating cylinder 10. The connection between the power cables 30 and 30 is completed by inserting 30a and 30a, respectively, and projecting the conductor tips of the connection end portions 30a and 30a from the spiral core 240 to connect to the electrical connection conductor 11. At this time, the connection end 30a can be easily inserted without receiving pressure from the inner surface of the rubber block insulating cylinder 10. Moreover, since the electrical connection conductor 11 is pressed from both sides by the spiral cores 240 and 240, the electrical connection conductor 11 is not displaced. By making the inner diameter of the spiral core 240 equal to or slightly larger than the outer diameter of the power cable 30, the cable insertion force can be greatly reduced. Such a reduction in insertion force can also solve the problem of causing the electrical connection conductor 11 to be displaced relative to the rubber block insulating cylinder 10.
When the insertion and connection of the power cables 30 and 30 is completed, the spiral core 240 is removed from the rubber block insulating cylinder 10 while being unwound, and the diameter of the rubber block insulating cylinder 10 is reduced and fixed to the connection end 30a. As compared with the case of the tapered pipe 140 in the second embodiment, it is possible to reduce the pulling force when removing.

Also in the second and third embodiments, it is preferable to provide a restricting portion on the insertion jig as in the first embodiment.
In the first to third embodiments, the rear end portion of the insertion jig is not limited to the illustrated one, and is appropriately configured to have a shape and size that can be easily gripped when inserting the power cable.

[Summary of effects of the embodiment]
According to the power cable connecting apparatus of the above embodiment, there are the following effects.
(A) At the power cable connection construction site, the connection end 30a of one power cable 30 is inserted from one end opening m1 to the center of the rubber block insulating cylinder 10, and the connection end 30a of another power cable 30 is inserted. Since the method of inserting from the other end opening m2 to the center of the rubber block insulating cylinder 10 is adopted, the inner diameter of the rubber block insulating cylinder 10 is increased so that the work of inserting the power cable is facilitated as in the prior art. There is no need to do it. There is no significant change in the outer diameter of the rubber block insulating cylinder 10 before and after being attached to the power cable 30, and a protective tube assembly for electrical shielding treatment and mechanical strength enhancement can be implemented in advance at the factory assembly. become. As a result, the amount of work and the work time at the power cable connection construction site are shortened.
(B) As described in (a), since the outer diameter of the rubber block insulating cylinder 10 does not change greatly before and after being attached to the power cable 30, permanent deformation and stress of the rubber block insulating cylinder due to the pre-expansion history. Since the degree of occurrence of relaxation is smaller than in the past, the rubber block mounting ratio ([Outer diameter attached to power cable (C in Table 1)]] [Rule outer diameter of rubber block insulating cylinder (Table Even if the ratio of 1) to A)] is reduced, a sufficient surface pressure can be secured between the power cable 30 and the rubber block insulating cylinder 10. Alternatively, when a conventional mounting rate is applied, a higher surface pressure can be obtained more stably.
(C) Since the electrical shielding layer 12 and the protective tube 14 are assembled at the factory, it is not necessary to inject a compound to fill a gap generated at the power cable connection construction site. This also leads to a reduction in the amount of work and work time at the construction site of the power cable connection.
(D) Since the position of the tip end of the connection end 30a of the power cable 30 is regulated at the central portion where the electrical connection conductor 11 is installed in the rubber block insulating cylinder 10, the assembly error at the power cable connection construction site ( The displacement of the mounting dimension) can be suppressed as compared with the conventional method described above, and an ideal design can be pursued by setting the axial dimensional tolerance of each part of the power cable connecting device 1 to be small. Therefore, waste of material can be eliminated and the power cable connecting portion can be configured more compactly.
(E) Protection is provided by inserting and inserting the insertion jig 40 (140, 240) used as a support jig for the hollow portion when forming a shielding structure or the like in the rubber block insulating cylinder 10 when the cable is inserted. The power cable 30 can be inserted without gripping the tube 14 (and thus without causing relative displacement between the rubber block insulating cylinder 10 and the protective tube 14). Further, by providing the insertion jig 40 (140, 240) with the restricting portions 40c1, 40c2, the insertion jig 40 is inserted from the normal position, and the electrical connection conductor 11 is attached to the rubber block insulating cylinder 10. It can also solve the problem of shifting.

DESCRIPTION OF SYMBOLS 1 Power cable connection apparatus 10 Rubber block insulation cylinder 11 Electrical connection conductor 11a Connection part 11b Connection part 12 Electrical shielding layer 13 Crimp terminal 14 Protection tube 15 Buffer material 16a, 16b Anticorrosion layer 17 Heat shrinkable tube 18 Anticorrosion tape 30 Power cable 30a connection end 32 conductor 33 slip-on connection terminal 34 anticorrosion layer 40 insertion jig 40a tip part m1 one end opening m2 other end opening 140 taper pipe (insertion jig)
240 Spiral core (insertion jig)

Claims (10)

An insulating cylinder attached to a conductor connecting portion connecting the conductors of the power cable;
An electrical shielding layer applied to the outer peripheral side of the insulating cylinder;
A protective tube provided on the outer peripheral side of the electrical shielding layer,
The insulating cylinder receives a connection end of one power cable inserted from one end opening of a hollow portion of the insulating cylinder, and receives a connection end of another power cable inserted from the other end opening. The conductors of the one power cable and the other power cable are configured to be connectable in the hollow portion,
An insertion jig is attached, and a distal end portion of the insertion jig is inserted into a receiving portion that receives the connection end portion formed in the hollow portion of the insulating cylinder,
In order to insert the connection end portion into the receiving portion when the power cable is connected, the rear end portion of the insertion jig extending from the receiving portion functions as a gripping portion, and the insertion jig is A power cable connecting device held so as to be removable from the receiving portion. An electric connecting conductor having two connecting portions and connecting the conductors of the power cable is installed in the hollow portion of the insulating cylinder, and one connecting portion of the electric connecting conductor is a connecting end of the one power cable. It is connectable with the connection terminal attached to the conductor tip of the part, and is arranged toward one end opening of the hollow part of the insulating cylinder, and the other connection part is a conductor of the connection end part of the other power cable. The power cable connecting device according to claim 1, wherein the power cable connecting device is connectable to a connection terminal attached to a distal end portion and is arranged toward the other end opening of the hollow portion of the insulating cylinder.   The said insertion jig has the control part for controlling that the said insulation cylinder approaches the rear-end part of the said insertion jig in the site | part outside the internal diameter range of the said insulation cylinder. 2. The power cable connecting device according to 2.   The power cable connection device according to any one of claims 1 to 3, wherein the insertion jig is a tapered pipe in which at least an outer diameter of the tip portion decreases in the insertion direction.   The connecting end of the power cable can be inserted into the receiving part by inserting the connecting end of the power cable into the pipe inserted into the receiving part, and the connecting end is inserted into the receiving part and the pipe. The power cable connecting device according to claim 4, wherein the pipe can be removed from the receiving portion in the inserted state.   The power cable connecting device according to any one of claims 1 to 3, wherein the insertion jig is a spiral core.   The connecting end of the power cable can be inserted into the receiving portion by inserting the connecting end of the power cable into the spiral core inserted into the receiving portion, and the connecting end can be inserted into the receiving portion and the spiral core. The power cable connecting device according to claim 6, wherein the spiral core can be removed from the receiving portion in a state of being inserted into the receiving portion.   The power cable connecting device according to any one of claims 1 to 7, wherein a buffer material is installed between the electrical shielding layer and the protective tube.   The power cable connecting device according to any one of claims 1 to 8, wherein an anticorrosion layer is provided on an outer peripheral side of the protective tube. An insulating cylinder attached to a conductor connecting portion connecting the conductors of the power cable;
An electrical shielding layer applied to the outer peripheral side of the insulating cylinder;
A protective tube provided on the outer peripheral side of the electrical shielding layer,
Insertion jig is attached, by using the insertion jig power cable connecting apparatus tip is inserted into accommodate receiving unit receives the connection end portion that will be formed in the hollow portion of the insulating cylinder of the power cables A power cable connection method for connecting each other,
After the electrical shielding layer and the protective tube are applied to the insulating cylinder and the insertion jig is inserted,
While holding the rear end portion extending from the receiving portion of the insertion jig to the outside, the connection end portion of one power cable is inserted from one end opening of the hollow portion of the insulating cylinder, and the other end opening is inserted. Inserting the connection end of the power cable and connecting the conductors of the one power cable and the other power cable within the hollow portion of the insulating cylinder, and
A power cable connecting method comprising: removing the insertion jig from the receiving portion.

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