JPS59188311A - Method of connecting conductor of internal cooling cable - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for linearly connecting conductors of an internally cooled cable having a sealed metal pipe around the inner periphery of the conductor.

(Technical Background of the Invention) In recent years, so-called internally cooled cables in which a circulation passage for a refrigerant such as 7 leon is provided between the conductor center, insulated wire core, and outer metal sheath have been put to trial use. In this case, a sealed metal pipe made of aluminum or the like is used as a refrigerant passage provided in the center of the conductor to prevent the refrigerant sealed inside from leaking to the outside.

Conventionally, the sealed metal pipe and conductor of such a cable are connected in the following manner.

That is, as shown in FIG. 1, first, the reinforcing tube 2 is inserted into a pair of sealed metal pipes 1 and 1' to be connected, spanning them, and in this state, the end of the sealed metal pipe 1°1' is inserted. and weld the abutting parts along the circumferential direction. Next, the conductors 3, 3' to be connected are connected in pairs to the sealed metal pipes 1.
, 1' and weld the abutting portions. Note that 4 and 5 in the figure indicate the welded portions of the sealed metal pipe and the conductor, respectively.

(Problems with the Background Art) However, in such a conventional method, not only is it difficult to weld the conductors 3 and 3' located below, but also the welding positions of the conductors 3 and 31 are not close to the closed metal pipe 1.1'. Since the welded part 4 is located above the welded part 4 of the conductor 3, 3', the welded part 4 deteriorates due to the heat generated during welding of the conductors 3, 3', and has the disadvantage that it cannot withstand the internal pressure of the refrigerant sealed in the pipe during use.

(Object of the Invention) The present invention has been made in order to eliminate these drawbacks, and provides a method for connecting conductors of internal cooling cables that does not impair the airtightness of a sealed metal pipe and can be operated satisfactorily. The purpose is to

(Summary of the Invention) The present invention involves cutting a conductor slightly longer so that the cut end of the conductor protrudes outward from the connecting end of the sealed metal pipe, and cutting the conductor in pairs at a position away from the outer peripheral surface of the sealed metal pipe. The method is characterized in that the abutting portions are welded, and then the welded conductors are arranged with the same diameter along the outer peripheral surface of the sealed metal pipe so that they do not overlap each other, that is, in a meandering manner.

(Embodiment of the Invention) The present invention will be described below based on the drawings of one embodiment. 1st
In FIG. 2, where the same parts as in the figure are given the same reference numerals, the conductor 3.3' to be connected, which has the sealed metal pipes 1 and 1' on its inner periphery, is connected to the end of the sealed metal vibrator 1.1'. It is cut slightly longer so that it protrudes outward. Next, after the ends of the sealed metal vibrators 1 and 1' are abutted and the abutted parts are welded, the conductors 3 and 3' to be connected are connected pair by pair to the outer periphery of the connected hermetically sealed metal vibrators 1°1'. They are abutted at a position slightly outward from the surface, and the abutted portions are welded.

Next, as shown in FIG. 3, the welded conductors 3, 3/pair are arranged in a meandering manner so that the extra length is pushed down onto the outer peripheral surface of the sealed metal pipes 1, 11. A conductor connection is obtained. In order to facilitate the connection of the conductor, it is desirable that the conductor be extremely blunted so as to give sufficient flexibility after cutting the conductor or beforehand during the manufacture of the cable.

(Effects of the Invention) As is clear from the above description, in the present invention, since the conductor welding work is performed at a position away from the outer peripheral surface of the inner sealed metal vibrator, the workability is not only good but also , There is little thermal influence on the welded part of sealed metal pipes when welding conductors. Therefore, thermal deterioration of the welded portion of the enclosed metal pipe hardly occurs, and it is possible to obtain an internal cooling cable that can sufficiently withstand a predetermined refrigerant filling pressure.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing a conventional method for connecting conductors of an internal cooling cable, Fig. 2 is an explanatory diagram showing a connection situation according to the conductor connection method of the present invention, and Fig. 3 is an explanatory diagram showing the state of conductors connected according to the present invention. FIG. 1 , 1' , ---- One sealed metal pipe 2 --
------------1----Reinforcement pipe 3, 3'----
-1 conductor 4, 5-----1 welded part

Claims (1)

[Claims] 1. When connecting the conductor of an internal cooling cable that has a sealed metal pipe inside the conductor, cut the conductor to be connected so that it slightly protrudes from the connection end of the sealed metal pipe,
A method for connecting conductors of an internal cooling cable, characterized in that the welded conductors are butt welded, and then the welded conductors are meandered along the outer circumferential surface of the hermetically sealed metal pipe so as not to overlap each other. 0