US1886786A - Electric cable - Google Patents

Description

Nov. 8, 1932. l. BRANTHWAITE ELECTRIC CABLE Filed oct. 24, 1931 @PEPE P4PE/12 IN VEN TOR. ma i WM@ ATTORNEYS.

I BY MMA/ Patented Nov. 8, 1932 Lamina;I

UNITED STATES PATENT oFfFrcE ISAAC :BEANTHWAI'IIE, 0F PASSAIC, NEW JERSEY, ASSIGNOR TO THE OXONITE-CAL- LENDER CABLE COMPANY, INCORPORATED, OF PATECRSON, NEW JERSEY, A. CORPO- RATION OF NEW JERSEY ELECTRIC CABLE Application mea october 24, 1981. serial No. 570,868.

This invention is directed to an improveg ment in lcable constructions and has among l lts ob]ects the provision of a construction whereby the movement' of the oil or other Huid insulation of the cable is increased, op-

15 eration improved and injury to the sheath A crepe paper holds more oil than the usual ltion wrapped helica paper used for cable purposes, the oil becomes more quickly distributed about the cable, and it responds readily to changes in temperature and pressure within the cable, thereby improving the operation.

In addition, crepe paper has better mechanical characteristics due to the greater stretch or elongation as compared with ordinary paper, and this makes the completed cable mechanically stronger.

Fig. 1 isa cross section of the length of one'type of cable constructed in accordance with my invention; and

Fig.f 2 is a similar view of another embodiment of the invention.

In stranded single conductor cables, as distinguished from multi-conductor cables, it has been suggested to lay up the strands of the conductor of the cable in such fashion as to provide a channel through the cent-er ,of the conductor for the flow of oil or other iluid insulation therethrough. The conductor is insulated lwith im regnated paper insulally about the same. A shielding tape is then a plied about this insulation and lead sheat applied to the exterior of the cable.

Such cable is usual commercial practice and my invention provides an improved construction as compared with such cables.

Referring to Fig. l ofthe drawing, l designates the stranded conductor of a single conductor cable. `It will be seen from the ndrawing that the strands of this conductor are laid up in such a manner as to leave a passageway or channel through the conductor. In accordance with myinvention I fill this passageway or channel, with crepe paper which I have designated 2. To the exterior of the conductor I apply impregnated -paper as insulation which may also be crepe paper, in whole or in part. To the exterior of this paper insulation I ap ly a shielding tape .4 and to the exterior of tliis tape a body -of crepe paper 5 as 'a channel directly under the exterior lead sheath 6. I have found in actual practice that by employin crepe paper in the assageway through t e conductor a much etter circulation of oil or other insulating luid is obtained than when material such as jute or ordinary paper is employed.

In the operation of oil impregnated cables the oil `increases in volume due to the heat generated by operation of lthe cable. This produces a pressure Within the cable which is transmitted to the lead sheath. In prior cables this pressure is a source of trouble and at times even ruptures the lead sheath It will be understood that I consider the,

use of crepe paper in one or all particulars mentioned as constltutmg my lnvention.

With respect to multi-conductor cables. It`

is customary in such cables to .enclose a plurality of separately insulated conductors ,within a lead sheath the voids between the sheath and the insulation of the conductors containing various types of material known commercially as fillers and impregnated with oil or other suitable insulatigcompound.

The embodiment of my invention illustrated in Fig. 2 is directed to improving slch constructions. Referring to this igure, 7 8 and 9 designate the three conductorsof a multi-conductor cable. Each of these conductors is insulated by impregnated insulation 10 and assembled in the usual manner as illustrated. T he voids between the three insulated conductors and between the insul ated conductors and the lead sheath 12 are filled with crepe paper designated 1l. It is understood, of course, as in the case of Fig. 1, the cable is linally filled with oil or other fluid insulating medium.

I iind that a multi-conductor cable con` Vstructed as just explained holds more oil, the oil remains more evenly distributed and the cable operation is much improved as compared with existing structures.

What I claim is: 1'. Electric cable construction comprising a conductor provided with a central passage- Way, a crepe paper liller for said passage- Way, a permeable impregnated crepe paper insulating envelope about the conductor, an exterior metallic sheath, and crepe paper intermediate the metallic `sheath and said insulating envelope. p

2. An electric cable construction comprising a conductor provided with a central passageway, a crepe paper ller for said passagevvay, a permeable impregnated crepe 'paper insulating envelope about the conductor, a metallic shielding tape about said insulating envelope, an vexterior metallic sheath,

and crepe paper intermediate the metallic sheath and said shielding tape. Y

This specification signed this 21st day of October, 1931.

ISAAC BRANTHWAITE.

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