JPH0638332A - Method and jig for fitting insulation tube to cable joint - Google Patents

Abstract

PURPOSE:To provide a method and jig for fitting an insulation tube being employed in the formation of plug-in type linear joint of rubber or plastic insulated cable with high workability and good electric performance. CONSTITUTION:After a CV cable 28, subjected to conductor connection and required treatment such as fitting of cable spacer, is fixed by means of cleats, a terminal insertion metal 18, an intermediate insertion metal 20, and the like are stopped or fitted at predetermined positions on the opposite ends of an insulation tube 17 and on the outer peripheral surface at an intermediate straight pipe section. Couplers 23 are then passed sequentially through four insertion holes of an insertion metal and coupled. After the coupler 23 is jointed, at the opposite ends thereof, to eye nuts 25 a main wire 26 connected with the eye nut 25 on one side is hauled horizontally by means of a winch thus moving the insulation tube 17 while keeping distances between respective positions and fitting the insulation tube 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of inserting an insulating tube into a cable connecting portion and an inserting jig, and particularly inserting an insulating tube into a plug-in linear connecting portion of a rubber or plastic insulating cable. The present invention relates to a method and a jig used for inserting and fitting such an insulating cylinder.

[0002]

2. Description of the Related Art In recent years, in the connection portion of rubber or plastic insulated cables such as CV cables (cross-linked polyethylene insulated cables), the size has been reduced and labor has been saved.
For the purpose of stabilizing characteristics and the like, a prefabricated type connecting portion has been widely introduced in which a rubber mold molded body is used in place of self-fusing tape winding for insulation treatment.

The structure of a plug-in type straight connecting portion which is a kind of such a prefabricated type connecting portion is shown below. That is,
In the plug-in type straight connecting portion of the CV cable, as shown in FIG. 8, the exposed conductors 2 of the two ends of the CV cable 1 are butted and are compression-connected by the conductor sleeve 3, and the conductor sleeve 3 is connected. A semi-conductive sleeve cover 4 is fitted on the top. Further, on the exposed insulator 5 of the CV cable 1, a cable spacer 6 made of an insulating rubber such as ethylene-propylene rubber (EPR) is used.
Has been fitted. Further, on the outside of these, a three-layer mold is formed across the cable spacers 6 on both sides by an inner semiconductive layer 7a such as a semiconductive EPR and an outer semiconductive layer 7b and an intermediate insulating layer 7c such as an EPR. Insulation cylinder 7
Is fitted, and a protective case 9 is fitted thereon via an insulating tubular spacer 8. It should be noted that vertical wall portions 7b 'are formed at both ends of the outer semiconductive layer 7b. Furthermore, taper-shaped protective case end caps 10 are attached to both ends of the protective case 9, respectively, and the other end of the end cap 10 is covered with a sheath slip stopper 11 and a waterproof tape winding layer 12. Each is fixed on the cable sheath 13. In the figure, reference numeral 6a is a semiconductive portion of the cable spacer, 1
4 is a ground wire, 15 is a winding layer of semiconductive tape, 1
Reference numeral 6 indicates a shielding layer.

Conventionally, in the formation of such a connecting portion, to insert the rubber mold insulating tube 7, after inserting the cable spacers 6 on the cable insulators 5 on both sides,
A method has been adopted in which the insulating cylinder 7 previously fitted in the cable end portion is moved to a predetermined position by manually pulling or pushing the cable spacer 6 on the cable spacer 6 in the axial direction of the cable.

[0005]

However, in recent years, it has become difficult to manually insert the insulating cylinder 7 as described above, due to the tendency of the insulating cylinder 7 to have a larger diameter and a longer length.
That is, in order to secure the insulation thickness and improve the insulation strength in response to the demand for higher voltage and larger capacity of power transmission, the insulation tube 7 has a large diameter. ． It has been designed and made longer. As a result, the contact area between the insulating cylinder 7 and the cable spacer 6 increases, and the frictional force when moving the insulating cylinder 7 on the cable spacer 6 also increases. Therefore, an efficient insertion method instead of the manual method can be used. It has been demanded.

The present invention has been made in view of these circumstances, and in forming a plug-in type straight connecting portion of a rubber or plastic insulated cable, an insulating portion having good workability and good electrical performance can be obtained. An object of the present invention is to provide a method for inserting a cylinder and an insertion jig that can be used for inserting such an insulating cylinder.

[0007]

SUMMARY OF THE INVENTION A method for inserting an insulating tube into a cable connecting portion according to the present invention is a cable spacer fitted on both sides of a cable insulating material on a conductor connecting portion of a rubber or plastic insulated cable. In the method of inserting a rubber-molded insulating tube over the insulation tube, an insertion jig is locked on the outer periphery of the insulating tube, and the insulation tube is mechanically pulled in the axial direction of the insulating tube. Is moved in the axial direction.

The insulation tube insertion jig according to the present invention has a rubber mold insulation over the conductor connection portion of the rubber or plastic insulation cable, straddling the cable spacers fitted on the cable insulators on both sides. In a jig for inserting a cylinder, a plurality of annular insertion fittings surrounding the outer circumference of the insulating cylinder and having an inner peripheral surface locked to the outer peripheral surface of the insulation cylinder, and a plurality of insertion fittings inserted between the insertion fittings. It is characterized by comprising a connecting means for connecting the metal fittings integrally while maintaining the metal fittings at a predetermined interval.

[0009]

In the method of inserting the cable-connecting portion into the insulating tube according to the present invention, the inserting jigs are locked at a plurality of positions on the outer periphery of both ends of the rubber-molded insulating tube and the intermediate straight pipe section. A mechanical traction force is applied to the insertion jig through a connecting wire or the like in the horizontal direction parallel to the axis of the cable. As a result, the distance between these insertion jigs is maintained and the insulating cylinder is moved while maintaining its shape, so that the insulating cylinder is not curved or deformed like axial compression. .
Therefore, electrical distortion does not occur in the insulating cylinder, and voids do not occur at the interface with the lower cable spacer, so that a connection portion with good electrical performance can be obtained. Also, the insertion work is easy.

Further, the insertion fitting jig of the present invention comprises a plurality of annular insertion fittings that are locked to the outer peripheral surface of the insulating cylinder, and a means for connecting these insertion fittings while keeping the mutual intervals constant. Since it is provided, it is possible to efficiently and satisfactorily perform the above-described work of inserting the insulating cylinder.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram schematically showing an embodiment of an insulating tube inserting jig of the present invention and an example of an insulating tube inserting method using such a jig. 2 and 3
Are enlarged front views and sectional views of the end insertion metal fittings constituting the insulating tube insertion jig of the embodiment, and FIGS. 4 and 5 are enlarged front views and sectional views of the intermediate insertion metal fittings. FIG. 6, FIG. 6 and FIG. 7 are also a front view and a cross-sectional view showing an enlarged side view of the fitting.

In these figures, reference numeral 17 indicates a rubber mold insulating cylinder formed by a three-layer rubber mold or the like, and has flat surfaces 17a perpendicular to the axis at both ends thereof.
Is formed, and a plurality of concave grooves are provided around the outer peripheral surface of the intermediate straight pipe portion at substantially equal intervals. Then, as shown in FIGS. 2 and 3, on the vertical flat surfaces 17a at both ends of the insulating cylinder 17 having such a structure, as shown in FIG. 2 and FIG.
8a-formed split annular end insert fitting 18
Are locked so that the surfaces on the non-protruding side are in contact with each other. Further, on at least one surface of each of the end insertion fittings 18, in order to integrally hold the fittings, a split ring-shaped fitting fitting 19 shown in FIGS. 6 and 7 is arranged so that the split position is shifted by 90 ° and stacked. To be done. Further, in the concave groove of the outer peripheral surface of the insulating cylinder 17, the intermediate insert metal fitting 20 having a split annular shape in which a thick fitting portion 20b is formed at the peripheral edge of the central opening 20a is fitted, as shown in FIGS. 4 and 5. Be worn. Further, at least one surface of these intermediate insertion metal fittings 20 is provided on at least one surface in order to make the integrated holding stronger, as shown in FIGS. 6 and 7.
Are placed one on top of the other with the split position shifted by 90 °. Furthermore, four insertion holes 21 formed at equal intervals near the outer periphery of the end insertion metal fitting 18, and four insertion holes 21 formed at equal intervals on the outer peripheral edges of the intermediate insertion metal fitting 20 and the mounting metal fitting 19 respectively. A connecting body 23 composed of four screw rods is inserted into the groove 22 in order, and is fixed by bolts 24 screwed into the screw rod at a certain interval. Eye nuts 25 are connected to both ends of these connecting bodies 23, and a main wire 26 is connected to the eye nut 25, and the main wire 26 is connected to a guide plate 27. The guide plate 27 is connected to a winch (not shown) via a tension meter 28, and is pulled by the winch in a horizontal direction along the axis of the insulating cylinder 17 with an appropriate tension while watching the tension meter 28. Is configured.

Using the insertion jig constructed as described above,
The insulating cylinder 17 is inserted and fitted as described below. That is, the cleats (insulators) 30 are fixed to both sides of the insulating cylinder 17 insertion position of the CV cable 29 to which the conductor is connected and the cable spacer is fitted on the cable insulator. . Then, one cleat 30 is fixed to a pole or the like in a manhole, and the other cleat 30 is fixed with a wire via a tension meter (not shown). Next, the end insertion fittings 18, the intermediate insertion fittings 20, and the mounting fittings 19 are locked or fitted at predetermined positions of both ends of the insulating cylinder 17 and the intermediate straight pipe portion, which are fitted on the cable in advance. Then
The connecting body 23 is passed through the four insertion holes 21 and the insertion grooves 22 of the insertion fittings 18 and 20 and the side fitting 19 in order, and is fixed by the bolts 24, and both ends of these connecting bodies 23 are connected to the eye nut 25, respectively. The main wire 26 connected to the eye nut 25 on one side
Is pulled by a winch in the horizontal direction parallel to the axis of the CV cable 29. In this way, the four connecting bodies 23 connected to the two upper and lower main wires 26 are respectively pulled in the horizontal direction to be fitted and attached to both ends of the insulating cylinder 17 and the outer periphery of the intermediate straight pipe portion. The same amount of horizontal traction force is applied to the end insertion fitting 18 and the intermediate insertion fitting 20. Therefore, since the distance between the respective portions of the insulating cylinder 17 to which the respective insertion fittings are attached is always kept constant and the spindle shape is maintained, the insulating cylinder 17 is inserted and fitted. In addition, the insulating cylinder 17 is not bent or deformed like compression in the axial direction. Therefore, a plug-in type linear connection part having good electrical performance is formed.

When the insulating cylinder 17 is pulled too much from the predetermined position, a cleat, a wire or the like is set at a position opposite to the above position, and the pulling fine adjustment is performed in the opposite direction.

[0016]

As described above, according to the method of inserting the insulating cylinder of the present invention, the insulating cylinder is not bent or deformed due to the axial compression, and the distance between the respective parts is always constant. Since the moving insertion is performed in the state of being kept, the plug-in type linear connecting portion having good workability and good electric performance is formed.

Further, according to the inserting jig of the present invention, the above-described inserting method of the insulating cylinder can be carried out efficiently and surely.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an embodiment of an insulating tube inserting jig of the present invention and an insulating tube inserting method in a cable connecting portion using such a jig.

FIG. 2 is a front view showing, in an enlarged manner, an end-portion fitting which constitutes the insulating tube fitting jig of the embodiment.

FIG. 3 is an enlarged sectional view of the end insertion fitting.

FIG. 4 is a front view showing, in an enlarged manner, an intermediate insertion fitting that constitutes the insulating tube insertion jig of the embodiment.

FIG. 5 is an enlarged cross-sectional view of the intermediate insert fitting.

FIG. 6 is an enlarged front view showing a side fitting that constitutes the insulating tube insertion jig of the embodiment.

FIG. 7 is an enlarged cross-sectional view of the side fitting.

FIG. 8 is a vertical cross-sectional view showing a structure of a plug-in type linear connecting portion of a conventional CV cable.

[Explanation of symbols]

1, 29 ... CV cable, 2 ... cable conductor, 3 ... conductor sleeve, 4 ... sleeve cover, 5 ... cable insulator, 6 ... cable spacer, 7, 17 ... Insulation cylinder, 8 ......... Insulation cylinder spacer, 9 ......... Protection case, 10 ...... Protection case end cap, 11 ......... Sheath slip prevention metal fitting, 12 ......... Waterproof tape winding layer, 13 ......... Cable sheath, 14 ... Ground wire, 15 ... Semi-conductive tape winding layer, 16 ... Shielding layer, 18 ... End insertion metal fitting, 19 ... Metal fitting, 20 ... Intermediate insert metal fitting, 21 ... Insertion hole, 22 ... Insertion groove,
23 ......... Connector, 24 ......... Bolt, 25 ...
… Eye nut, 26 ……… Main wire, 27 ……… Guide plate, 28 ……… Tension meter, 3
0 ......... Cleat.

Claims (2)

[Claims] 1. A method of inserting a rubber-molded insulating cylinder over a conductor connecting portion of a rubber or plastic insulating cable, straddling cable spacers fitted over the cable insulators on both sides, wherein An insulating tube insertion of a cable connecting portion, characterized in that an inserting jig is locked on an outer periphery, and the insulating tube is moved in the axial direction while applying a mechanical pulling force to the inserting jig in the axial direction of the cable. Method. 2. A jig for inserting a rubber-molded insulating cylinder over a conductor connecting portion of a rubber or plastic insulating cable, straddling cable spacers fitted on the cable insulators on both sides, and wherein the insulating cylinder is inserted. A plurality of annular insert fittings that surround the outer circumference and whose inner peripheral surface is locked to the outer peripheral surface of the insulating cylinder, and are integrally inserted while being inserted between the insert fittings at a predetermined interval. An insulating tube insertion jig, characterized in that it comprises a connecting means.