US1734700A

US1734700A - Coated core

Info

Publication number: US1734700A
Application number: US643557A
Authority: US
Inventors: Walker Howard George
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1923-06-05
Filing date: 1923-06-05
Publication date: 1929-11-05
Anticipated expiration: 1946-11-05

Description

Patented llov. A5, 1929 UNITED STATES vParri-:N11 ori-Ica `HOWARD GEORGE WALKER, OF BERWYN, ILLINOIS, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, QF NEW YORK, N. Y., ACORPORATION OF NEW YORK COATED CORE Application med June 5,

. This invention relates to improvements in coated cores, and more particularly to electrical conductors vcoated with an insulat ing material which is impervious to moisture.

An object of theinvention is to-provide an electrical conductor. with an insulating material havin the desirable moisture-proof qualities of rub r, and in addition one which has low dielectric losses, is flexible and sufloiciently tough and durable to resist abrasion in handling.

Another object of the invention is to provide an electrical conductor with a coating of insulating material which is impervious 15 to moisture, the coating being of a type that it may be rapidly applied and including indients which are less expensive than the mgredients previousl used in insulating materials having equiva ent physical, dielectric, and moisture-proofing qualities. v An article made in accordance with the resent invention may comprise a core, preerably in strand form and, in cases where the finished article serves as an electrical conductor, of electrical conducting metal such as co per, coated with fibrous material which may e applied in any suitable manner. Although the fibrous material may be applied as a strand serving, as a braided covering, or both,or applied 1n some other manner, I preferably-coat the metallic core with pulp made of some cheap material such as wood, manila,

jute, esparto, or hemp, but the pulp may when desired be formed of rag, cotton, linen, asbestos, etc. This pulpous material is preferably applied to the core by the Ymethod and apparatus disclosed 1n Patents Nos. 1,615,416 and 1,615,417, issued on January 25, 1927 to H. G. Walker et al., respectively, wherein the pulpous material is held on the core solely by an intermingling of the fibers thereof. The coated coreis then impregnated with rubber latex which is a product of the rubber tree containing some water, or it may '50 The impregnation maybe accomplished by rubber latex each of the fibers of the pul ous be found preferable in some instances to dilute- 1923. serial no. 43,55?.

Vcore a plurality of times, drying the coating between each immersion in order to cause a thorough impregnation thereof. Other methods of im regnation may be employed as by the use o vacuum or pressure in a well known manner. i In impregnating the pulpous material with material is saturated with the latex w ich renders the fibers to an extent elastic. The elasticqualityngiven the Iibers and the cement- -ing'action of the rubber causes the pulpousf material to resist abrasion as well as i11'v 7o creases the iiexibility of the coating.- A

Electrical conductors coated Withlpu-lpous material impregnated with rubber latex may be used finder conditions approximating those to which ordinary rubber covered wiret is subjected. Conductors so coated may be used to advantage'in' the manufacture of telephone switchboard cable since the coating is moisture-pro0,`has-low dielectric losses, and is tough enough to resist abrasion during the handling of the cable in applying it to the switchboard. The simplicity of the method of producing and applying the insulation to an electrical conductor, as well as the cheapness of g5 the ingredients employed, results in an electrical conductor considerablyless expensive than conductors heretofore provided with an insulation having similar physical, insulat A., ing, and moisture-proof characteristics. In the accompanying drawing illustrating an electrical. conductor made in accordance with the invention, the reference numeral' indicates a strand-of conducting materiah,V preferably of copper, which is coated with pulpous material preferabl applied by the method and apparatus disclosed.; in the Walker-March patents hereinbeforereferred to. The insulating material as shown in the drawing cut away to more clearlyshow the" character thereof, and the reference numeral 10 indicates a portion of the pulpousmaterial unimpregnated, while the reference numeral 15 indicates the said material after it has been impregnated with rubber introduced by an emulsionv free from sulphur.

What is claimed isz 1. 'An electrical conductor comprising a metallic strand znd la, continuous, homlilageneous, integra coating engagin t e strand, consisting of felted fibrous pulgp free of adhesive material impregnated with a rubber emulsion.

,2. An 4electrical conductor comprising a metallic strand and a continuous, homogeneous', integral coating enclosing the strand, consisting solely of sel'y felted and matted paper impregnated' with a rubber emulsion.

3.- An electrical conductor comprising ay metallic strand and a continuous, homogeneous, ,interah flexible coating` enclosmg the stra'n ,consisting of loosely felted fibrous paper free of adhesive vmaterial impregnated withrubber introduced in an emulsion.

In witness whereof, I hereunto subscribe my name this 23 day of May A. D., 1923.

HOWARD GEORGE WALKER.