JP3287748B2 - Dustproof device for prefabricated joint insulation unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dustproof device for an insulating unit used for a prefabricated joint of a power cable.

[0002]

2. Description of the Related Art When a power cable is connected by a prefabricated joint, a dustproof hood is used to prevent foreign matter from entering an interface between an insulating unit and a stress cone. 2 (A) to 2 (F) show a conventional power cable prefab joint method using a dustproof hood. In the figure, 11 is a cross-linked polyethylene insulated power cable, 13 is a conductor connecting portion of the power cable 11, 15 is an epoxy insulating unit, and 17 is a stress cone.

[0003] As shown in FIG.
A dust-proof hood 19 is arranged on the outer periphery of the end portion in a state contracted in the longitudinal direction. One end of the dustproof hood 19 is fixed to the insulating unit 15 by a suitable fastening member 21. A protective pack 23 is provided on the inner peripheral surface of the insulating unit 15.
Is stuck. On the other hand, another dustproof hood 25 is put on the stress cone 17.

In FIG. 2A, after the stress cone 17 and the insulation unit 15 are mounted on the outer periphery of the power cable 11, a conductor connection part 13 is formed, and the insulation unit 15 is pulled back to the center part so that the conductor connection part 13 is formed. Shows the state fixed to. Thereafter, the dust hood 19 is stretched to cover the stress cone 17 as shown in (B), and then the stress cone 17 is pushed halfway by the push pipe 27. Next, as shown in (C), the user puts his hand in the dustproof hood 19 and removes the protective pack 23 on the inner surface of the insulating unit 15 and the dustproof hood 25 on the stress cone 17.

Next, as shown in (D), the stress cone 17 is pushed in from the outside of the dustproof hood 19 by the pushing pipe 27. When the stress cone 17 is pushed all the way, (E)
As described above, the insulating unit 15 and the stress cone 17 are in close contact with each other, so that the push pipe 27 is once returned to remove the dust hood 19. Finally, as shown in (F), the push pipe 27 is applied to the stress cone 17 to perform compression by a spring. Conventionally, connection work has been performed while preventing foreign matter from entering the interface between the insulating unit and the stress cone as described above.

[0006]

Conventionally, since the dust hood is directly attached to the outer periphery of the end of the insulating unit, foreign matter on the outer peripheral surface (protective copper tube) of the insulating unit may adhere to the inner surface of the dust hood. It has been difficult to reliably prevent foreign matter from being involved.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a dustproof device for an insulating unit which does not cause foreign matter on the outer peripheral surface of the insulating unit to adhere to the inner surface of the dustproof hood.

[0008]

According to the present invention, there is provided a dust-proofing device for an insulating unit, wherein a dust-proof hood in a longitudinally contracted state is arranged on an outer periphery of a cylindrical body mounted on an outer periphery of an end portion of the insulating unit. One end of the dustproof hood is fixed to the outer periphery of the cylindrical body, and a cover is provided so as to cover the dustproof hood.

[0009]

This dustproof device is used by mounting a cylindrical body on the outer periphery of the end of the insulating unit. Since the dustproof hood is disposed on the cylindrical body and covered by the cover, there is no possibility that foreign matter will adhere to the dustproof hood as it is. The cover is torn (or removed) only during the connection operation when the dust hood is extended. Therefore, there is no possibility that foreign matter will adhere to the inner surface of the dustproof hood until the dust hood is stretched to cover the stress cone, and the foreign matter can be more reliably prevented from being involved. In addition, since the dust proofing device can be inspected beforehand with an X-ray or the like at a factory before the dust proofing device is mounted on the outer periphery of the end of the insulating unit, it is possible to ensure that no foreign matter is contained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to FIG. The dustproof device 31 according to the present invention includes a plastic cylindrical body 33 mounted on the outer periphery of the end of the insulating unit 15.
It has. A dustproof hood 19 contracted in the longitudinal direction is disposed on the outer periphery of the cylindrical body 33.
Is fixed to the outer periphery of the cylindrical body 33 by a fastening member 21 (or an adhesive). Further, a cover 35 made of a plastic film is put on the outer periphery of the dust hood 19, and both ends of the cover 35 are sealed on the cylindrical body 33.
That is, since the dustproof hood 19 is hermetically sealed by the cylindrical body 33 and the cover 35, there is no possibility that foreign matter adheres to the dustproof hood 19.

As shown in FIG. 1, the dust-proof device 31 is used by being attached to the outer periphery of the end of the insulating unit 15. When the dustproof hood 19 is stretched during the connection work (stage B in FIG. 2), the cover 35 is cut out and the dustproof hood 19 is stretched. Therefore, there is little possibility that foreign matter enters the inside of the dustproof hood 19 until the dustproof hood 19 is extended.

[0012]

As described above, when the dust protector for an insulating unit according to the present invention is used, there is little possibility that foreign matter enters the inside of the dust hood, so that the insulating property of the prefabricated joint is not reduced by the foreign matter. A highly reliable connection can be made.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a dustproof device according to an embodiment of the present invention mounted on an insulating unit.

FIGS. 2A to 2F are cross-sectional views showing a conventional prefabricated joint method in the order of steps.

[Explanation of symbols]

 11: Power cable 13: Conductor connection part 15: Insulation unit 17: Stress cone 19: Dust-proof hood 31: Dust-proof tool 33: Cylindrical body 35: Cover

Claims (1)

(57) [Claims] A dustproof hood (19) in a longitudinally contracted state is disposed on the outer periphery of a cylindrical body (33) mounted on the outer periphery of an end of an insulating unit (15). ) Is fixed to the outer periphery of the cylindrical body (33), and is covered with a cover (35) so as to cover the dustproof hood (19).