GB273167A - Improvements in and relating to electric multi-conductor cables - Google Patents

Abstract

273,167. Sonnenfeld, H. June 25, 1926, [Convention date]. Cables of special cross - section. - The outer covering and lead sheathing of a cable having a number of conductors is not made circular in crosssection, as usual, but is made to conform closely to the outer surface of the conductors in order to reduce the quantity of lead and insulating material required. Fig. 2 shows a three-core cable in which the conductors M are covered with the usual insulation J and are assembled with a padding C4 of insulating material between them. The belt insulation P, the lead sheath 0, and the armouring P2 are shaped as shown, thus requiring less material than would be necessary if the casing were cylindrical. The padding C, which fils the spaces between the conductors and the casing, also requires less material. The use of less material enables the heat generated by the cable to be dissipated more easily. Armouring.-In sheathing the cable, the lead press is provided with suitably shaped dies and counter dies, and the cable drums can be rotated if the conductors are to be twisted. Alternatively, the dies and counter dies can be rotated in the press. In another method, the dies are of circular cross-section and produce a sheath which has a circumference equal in length to that of the required sheath. The lead cylinder, as it forms, shapes itself to the outline of the cable.