Method of manufacturing waterproof shielded cable

Abstract

A waterproof shielded cable is disclosed having a metallic shield formed with a longitudinal seam surrounding a core. A strip of material overlays the metallic shield seam with side edges located to each side of the seam. An extruded plastic jacket overlays the metallic shield and strip of material with the jacket being in intimate contact with the shield and with a principle surface of the strip of material but spaced from the strip side edges. A method is also disclosed for manufacturing a shielded cable which comprises the step of wrapping sheet metal about a cable core with the sheet metal edges overlapped to form a shield with a longitudinal seam. The shield seam is overlayed with a strip of material of a type characterized by being shrinkable when heated above a predetermined temperature, and with the strip edges straddling the shield seam. A plastic jacket is extruded onto the shielded core and strip of material at a temperature in excess of the predetermined temperature. The plastic jacket is cooled by conducting heat from the jacket into an ambient cooling medium and into the core through the strip of material and shield whereupon the strip of material becomes heated and shrinks drawing the strip edges towards the shield seam to leave gaps bounded by the strip edges, the shield and the jacket. During formation the gaps are filled with a flooding compound having a lower thermal conductivity than the surrounding materials.