US1993424A - Cable - Google Patents

Description

March 5, 1935. H WEBER 1,993,424

CABLE Filed June 20, 1930 INVENTOR flan/are H Weber:

7 ATTORNEYS Patented Mar. 5, 1935 UNITED'STATES PATENT OFFICE CABLE Howard H. Weber, Rome, N. Y., assignor to General Cable Corporation, New York, N. Y., a corporation of New Jersey Application June 20, 1930, Serial No. 462,458

9 Claims. (01. 173-267) The present invention relates to improvements ture-proofing compound, and a similar compound in insulated electrical conductors. may be applied to the jacket covering the ground In the distribution of electrical energy between return conductor 4. The conductors thus covered consumers premises and trunk cables on poles, are assembled together. If desired, the valleys 5 a type of cable is used which is known as "service between the conductors may be partially or en- 5 cable. Ordinarily, this cable is formed of a plutirely filled with jute strands 9 which have been rality of twisted insulated conductors which may pressure impregnated with a suitable waterproofbe' housed in a fibrous jacket and the valleys filled ing compound. with fibrous strands. Due to the relatively low Conveniently, the assembled conductors are 10 insulating value of the covering of such cable, it covered with a coating 10 of a migratory putty 10 has been necessary, heretofore, to run the cable or compound, a sufiicient amount being applied aerially from the pole to a point on the conso as to complete the filling of the valleys between sumers premises and then directly into the attic the conductors, or, in the event that the filler or down into the ground through a conduit and strands 9 are not used, to completely fill the vall5 into the cellar. Generally, it is preferable to leys. This caulking compound is preferably enter the premises through the cellar butthe formed of a base of a fatty acid pitch, such as cost of the necessary conduit and the labor stearin pitch, and a mineral filler, such as a short charges for installation have been prohibitive to fiber silicate of magnesia, as set forth in the cothe average consumer. pending application of Frank M. Potter, Serial No.

0 Among the objects of the present invention, 251,767, filed February 4,1928 and patented April therefore, is the provision of a cable which meets 18, 1933 No. 1,904,527. The magnesium silicate, the above conditions, as well as others enumerated which is in a finely divided state, added to the in the following specification; that is to say, an pitch in the amount required to give the desired inexpensive, flexible cable of relatively high diconsistency, which, preferably, at normal atmoselectric strength and exceedingly rugged conpheric temperatures, is about like glazing putty, 25 struction, which may be installed aerially or unand. at 300 F. about like .cold molasses. The derground from an adjacent pole to the con amount of magnesium silicate added varies with sumers premises without the usual protective the consistency of the pitch but it is between 10% conduit. It is understood that while this invenand 20% of the whole. It a putty of a higher vistion has been developed for use in connection with cosity is desired, fibre asbestos may also be added 30 service cable, it readily lends itself to a variety to the magnesium silicate as a filler. Other minof other applications, as will be apparent to those eral fillers, such as alumina, ground quartz, mica skilled in the art. or magnesium oxide may be substituted for the Other objects of the invention will be apparent magnesium silicate if desired. from the following specification, wherein a pre- The resultant compound is extremely resistant 35 ferred and illustrative embodiment of the invento heat and to oxidation, inasmuch as each indition has been selected for description. In the acvidual substance is almost completely oxidized companying drawing before being combined. Moreover, this oxida- The single figure of the drawing shows a short tionand moisture-resistant putty does not besection of insulated conductor, wherein the sevcome brittle in cold weather nor unduly soft in 40 eral protective sheaths or jackets are progreshot weather. It is also noted that since the sively removed to illustrate the entire construcputty maintains its fluidity, it follows that it tion and assembly thereof. tends to flow toward and heal or seal any bruise Referring to the preferred and illustrative emor rupture which may later be made to the adjabodiment of the invention shown in the single cent conductor coverings. 45

figure of the drawing, a pair of metallic conduc- Preferably, sealing or barrier means 11 is potors 1 and 2 are covered with an insulating comsitioned around the coating 10 of putty. This pound 3 preferably of vulcanized rubber, and a means may take the form of a sheath of relathird metallic conductor 4, which conveniently tively thin crimped or crepe paper. Convenientserves as a ground return conductor, is provided ly, one or more sheets of such paper are applied 50 with a fibrous jacket 5. This jacket may conlongitudinally, with adjacent side edges overlapveniently comprise a paper wrapping 6 and a ping. In this way, the putty is maintained imbraided covering 7. Each of the rubber-covered mediately adjacent to the separately insulated conductors is provided with a fibrous jacket 8 conductors and in the valleys therebetween, and

which has incorporated therein a suitable moisoutward migration of the putty is prevented. 55

Preferably, the assembled conductors are afforded additional mechanical protection by means of a flexible metallic armor 12, which may take the form of a spiral wrapping of metallic tape, wherein the side edges of adjacent convolutions are interlocked. Conveniently, the outer surface of the metallic armor 12 is covered with a coating 13 of the oxidationand moisture-resistant compound. This coating, by reason of its migratory characteristic, tends to seal the line-of connection between the side edges of adjacent convolutions of the metallic tape. At the same time, the putty protects the metallic armor 12 from corrosion since it covers the outer surface thereof and seals the same from moisture.

In order to prevent the outward migration of the putty coating 13, barrier or sealing means 14 is provided, which is similar to that at 11, being formed conveniently of a plurality of longitudinal wrappings of relatively thin crepe paper positioned so that the side edges thereof overlap. The cable thus constructed is preferably provided with an outer protective jacket 15, such as a fabric braid provided with a waterproofing saturant of, say, soft wax.

Preferably, a tough, skin-like covering 16 is positioned over the outer braid 15. This covering may comprise a coating of paint, such as is disclosed in the aforesaid application. As therein stated, the paint may be formed of a metallic oxide, such as red iron oxide, litharge, alumina, magnesium oxide, etc. This metallic oxide is mixed with a specially prepared oxidizable oil which may include boiled linseed oil, partially polymerized.China-wood oil, stearic acid and zinc resinate.

This paint, when dry, provides a tough, waterproof skin, which is eflfective to prevent migration of the saturant used'in theouter jacket 15. The paint also protects the fibrous jacket 15 from the deteriorating effect of the ultra-violet rays; and the germicide, which is contained in the paint, resists bacterial growth especially in the adjacent fibrous coverings. Weather conditions over a long period of time have substantially no effect on the paint, and it is especially resistant 'to acids and alkalis, such as are frequently found in the atmosphere. The paint further affords the insulation protection against attacks by insects and the like. If desired, the finished cable may be provided with a coating 17 of paraflin.

It will be observed that the metallic conductors are afforded substantial electrical and mechanical protection, permitting the ready installation of the cable underground without the usual expensive conduit. At the same time, the cable is of relatively inexpensive construction. Hence, the cabling service charges between an adjacent pole trunk cable and the consumers premises are reduced to a Although only one embodiment of the invention has been shown and described herein, it will be understood that the invention may be variously modified and embodied within the scope of the subjoined claims.

I claim:

1. An article of manufacture comprising, in combination, an electrical conductor, and protective means therefor including a metallic armor, a self-sealing oxidationand moisture-resistant plastic compound, an outer jacket and a tough, waterproofing coating of metallic oxide paint.

2. An article of manufacture comprising in combination an electrical conductor, a cover therefor, a protective, helically wound metallic armor surrounding said cover, a layer of corrosion-resistant and moistureproof fatty acid pitch plastic coating material closely adhering to and covering said metallic armor, an outer fibrous cover for said coating material, and an impermeable barrier within said fibrous cover and surrounding said coating material to prevent said material from penetrating said outer fibrous cover.

3'. An article of manufacture comprising in combination an electrical conductor, a cover therefor, a protective armor comprising a helically wound metallic tape surrounding said cover, a layer of corrosion-resistant and moistureproof fatty acid pitch plastic coating material closely adhering to and covering said metallic,armor, an outer fibrous cover over said coating material, and an impermeable paper barrier within said fibrous cover and surrounding said coating material to prevent said material from penetrating said outer fibrous cover.

4. An article of manufacture comprising in combination an electrical conductor, a cover therefor, a layer of corrosion-resistant and moistureproof plastic coating material surrounding said cover, a protective helically wound metallic armor surrounding said coating material, an impermeable barrier between said armor and said coating material for preventing outward migration of said material, a second layer of corrosionresistant and moistureproof plastic coating material closely adhering to and covering said metallic armor, an outer fibrous cover for said coating material, and an impermeable barrier within said fibrous cover and surrounding said coating material to prevent said material from penetrating said outer fibrous cover.

5. An article of manufacture comprising in combination a plurality of insulated electrical conductors arranged together to form valleys therebetween, strands located in said valleys so as to at least partially fill the same, a layer of corrosion-resistant and moistureproof plastic coating material surrounding said conductors and completing the filling of said valleys, a protective metallic armor surrounding said layer of coating material, a second layer of said coating material closely adhering to and covering said metallic armor, an outer fibrous cover for said coating material, and a tough waterproofing coating of metallic oxide paint surrounding said fibrous cover.

6. An article of manufacture comprising in combination a plurality of insulated electrical conductors arranged together so as to form valleys therebetween, strands located in said valleys so as to at least partially fill the same, a layer of corrosion-resistant and moistureproof plastic coating material surrounding said conductors and completing the filling of said valleys, an impermeable paper barrier surrounding said plastic coating material, a protective metallic armor surrounding said paper barrier, a second layer of corrosion-resistant and moistureproof plastic coating material closely adhering to and covering said metallic armor, an outer fibrous cover for said coating material, and an impermeable barrier within said fibrous cover and surrounding said coating material to prevent said material from penetrating said outer fibrous cover.

7. An article of manufacture comprising, in combination, a plurality of insulated electrical conductors assembled to form valleys therebetween, strands located in said valleys, a layer of insulating material electrically and mechanically protecting the assembled conductors, a metallic armor surrounding the conductors and overlying said layer, a layer of moisture-resistant plastic compound surrounding the armored conductors, a barrier of paper impermeable to said compound overlying said last mentioned layer, and a surrounding braided jacket coated with a moistureresistant compound.

8. An article 01' manufacture comprising, in combination, an electrical conductor, and protective means therefor including an interlocking, helically wound metallic armor, a layer of moisture-resistant plastic compound and a barrier of paper impermeable to said compound underneath said metallic armor, a second layer of moistureresistant plastic compound and a second barrier of paper impermeable to said last mentioned compound over said metallic armor, and an outer braided jacket coated with a moisture-resistant compound.

9. An article of manufacture comprising, in combination, a plurality of insulated electrical conductors assembled to form valleys therebetween, filler material in said valleys, a protective covering over the assembled conductors, an overlapping helically wound metallic armor surrounding the assembled conductors, a protective covering over the metallic armor, a surrounding braided jacket coated with a moisture-resistant compound, and a thin paper barrier between said metallic armor and one of said protective coverings.

HOWARD H. WEBER.

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