GB490243A - Improvements in or relating to tubular bodies for use as components of electric cables or conductors - Google Patents

Abstract

490,243. Cables. SIEMENS & HALSKE AKT.-GES. Feb. 26, 1937, Nos. 5903, 5904, 5905, 5906, 5907, 5908, 5909, 5910, 5911, 5912, and 5913. Convention dates, March 19, 1936, April 27, 1936, Sept. 26, 1936, Oct. 24, 1936, Nov. 27, 1936, Dec. 10, 1936, Dec. 19, 1936, Jan. 22, 1937, Feb. 18, 1937, Feb. 22, 1937, and Feb. 22, 1937. [Class 36] A tubular body, formed of flexible metal or of firm but flexible insulating material, for use in a cable, e.g. as a conductor, screen, armouring, pressure protective covering, or insulating sleeve, consists of a band bent about a longitudinal axis into tubular form or a plurality of arcuate bands assembled into tubular form, the edges of the band or assembled bands either abutting and, if desired, being welded together, or overlapping circumferentially without being folded together. The body is rendered flexible by widely spaced transverse grooves or group of grooves, or by a continuous groove or grooves having a long pitch. The band or bands may be arranged parallel to the cable axis or may extend helically with a long lay. Fig. 1 shows a coaxial air-space insulated cable having an outer conductor 11 formed by two arcuate bands held together by a binding 15 and formed with transverse grooves' 12. The inner conductor 10 is supported by insulators 13 each having a groove 14 which is engaged by the internal ridge formed by the grooves 12. In a modified construction the bands are formed with pairs of grooves between which the insulators, in the form of discs, are held. The insulators may be of such form, e.g. as shown in Fig. 12, that they may be permanently attached to the outer conductor bands 54. The inner conductor 57 may also be permanently attached to the insulators 56. To prevent the edges of the bands from sliding inwardly over one another the grooves of the bands may be staggered, or the edges of the bands may be flanged, corrugated, or provided with indentations. To prevent contact between the inner and outer conductors thin insulating sheets or shells may be arranged in the ungrooved portions of the outer conductor bands. The grooves may be provided with longitudinal slots to increase the flexibility of the band. Fig. 26 shows grooved and slitted insulating tubes 113 wound about a conductor 112 to provide an air-space insulation. In a modified construction the conductor is supported within an insulating tube by slitted grooves in the tube. In the construction shown in Fig. 36, the tubular body is formed of bands 173, 174 having outwardly directed grooves 175, 176 respectively. The tubular body may have both inwardly and outwardly directed grooves, Fig. 49, showing a band from which such a body may be formed.