GB774204A - Improvements in or relating to electric cables - Google Patents

Abstract

774,204. Cables; couplings. ELECTRIC & MUSICAL INDUSTRIES, Ltd. July 15,1955 [July 27, 1954], No. 21846/54. Classes 36 and 38 (1). A high-frequency power cable 1 comprises spaced inner and outer flexible, fluid-impervious dielectric conduits 2, 3 and flexible tubular inner and outer conductors 4, 5 fitting closely within and over the conduit 2 respectively, so that cooling fluid can circulate through the conductor 4 and between the conductor 5 and conduit 3. The conductors may comprise braided sleeves of fine wires, which may be insulated, and a longitudinally-ribbed flexible core may be disposed within the conductor 4 to maintain its shape. A termination for the cable comprises inner and outer terminals, the inner tubular terminal 11 having a reduced end 12 fitting into conductor 4. The outer end of terminal 11 forms a conical seat for a union 16. Clamping ring 20 joins the end of conduit 2 to the terminal 11 in a fluid-tight manner. The outer terminal comprises a metal sleeve 21 carrying a metal flange 23 the outer face of which is recessed to receive a gland 24 carrying a sealing ring 25, the gland being secured to the flange by screws. A collar 13, slidable on terminal 11, is forced into the outwardly tapered bore of the gland so as to form a fluid-tight seal between conduit 2 and terminal 21. A shell 26 is disposed around terminal 21 to form an annular passage 30. The inner end 27 of the shell is fitted with conduit 3 and secured in a fluidtight manner by clamping ring 28. The outer end 31 of the shell is secured to the flange 23 in a fluid-tight manner. An outlet 32 in flange 23 communicates with passage 30 and has a straight union 34 secured therein. The union 16 is shaped so that the outer ends 35, 36 of the unions are symmetrically disposed about the axis of the terminal 11. An insulating plate 42 and cylindrical housing 43 complete the termination, the latter fitting over a wooden handle 44 surrounding the end of the cable. Cooling fluid circulates through the conduit 2, through the apparatus being supplied, such as the work coil of an induction heating apparatus, and back between conduits 2, 3.