摘要 |
979,833. Insulating cable and wire Joints. STANDARD TELEPHONES & CABLES Ltd. July 26, 1963, No. 29707/63. Heading H2E. A method of jointing electric cables 1, 2 (Fig. 1) having organic thermoplastic insulation, includes the steps of placing a tube 6 of organic thermoplastic material over a bare conductor joint 5 and over a portion of each insulating sheath, then covering only the end portions of the tube 7, 8 with heat-shrinkable thermoplastic material 9, 10, having a higher melting point than the insulating sheaths and the tube 6, and then heating the heat-shrinkable material to cause it to shrink and fuse the ends of the tube with the insulation (Fig. 2). The heat-shrinkable coverings 9, 10 may be in the form of sleeves of irradiated thermoplastic material, which may be polythene. The sleeves have previously been expanded when hot, and cooled such as to retain them in an expanded state. The cable cones 3, 4 are joined by a compression ferrule 5 or by soldering &c. After assembling, the sleeves 9, 10 are gripped by heated plier jaws 11, 12 until they have shrunk to their original dimensions. The pliers are removed, and the molten tube ends 7, 8 and insulating sleeves allowed to cool and fuse. The sleeves and tube may be of polyvinyl chloride. For ease of positioning, the tube 6 is preferably translucent. Instead of the sleeves 9, 10 wrappings of heat-shrinkable thermoplastic tape may be used. |