MANUFACTURE OF THIN ELECTRIC WIRE WITH FOAMED INSULATOR

• Main Authors: SHIMIZU MASAZUMI, OTSUKI HIDEO, ABE MASAHIRO
• Format: Patent
• Language: English
• Published: 08.01.1993
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BASIC ELECTRIC ELEMENTS; CABLES; CONDUCTORS; ELECTRICITY; INSULATORS; PERFORMING OPERATIONS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING ORDIELECTRIC PROPERTIES; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PURPOSE:To prevent the appearance from being roughened, reduce severance of the core covering in high speed operation, and enable quickening of the extruding process by performing extrusion while lubricant is supplied to the inner wall surface of a die of extruding machine. CONSTITUTION:Plastic material including a foaming agent is extruded onto a conductor and left foaming to form a thin electric wire, wherein the extrusion molding is conducted while lubricant is supplied to the inner wall surface of the die of extruding machine 1. Oil or gas is used for lubricant, and when the former is used, an ordinary oil in hydrocarbon series, an inorganic sili-U oil, etc., is used, because these are not likely to make chemical reaction with the die or plastic used in foaming extrusion, to permeate the die 5 or plastic, and to pyrolyze at the time of extrusion. When gas is used, nitrogen, air, carbon dioxide gas, etc., is used because they meet the same conditions as above, which is considered applicable even here, and because they are unharmful to the human body. Thereby the appearance is prevented from being roughened, severance of the core covering precluded, and high speed operation ensured.