RUNNERLESS INJECTION MOLDING EQUIPMENT OF ARMATURE FOR FLAT TYPE MOTOR

摘要

PURPOSE:To utterly eliminate resin loss and make finishing unnecessary and consequent ly make it possible to save resource and power as a whole by a method wherein a resin molded layer is formed on an armature coil by injecting polyphenylene sulfide resin under very low pressure from spires. CONSTITUTION:The temperature of the resin in a manifold 5 is retained and controlled at 350 deg.C by means of cartridge heaters, which are divided into two systems. The resin, which has passed through the manifold 5, passes through annular gaps, each of which is formed between each of spires 1 and its casing 2, and stagnates temporar ily. The temperature of the resin in said gap is retained and controlled by means of a heater built in the spire 1. The gate land part 1A of the resin is solidified by being cooled with molds 10 and 16 excluding at injection and injected in a housing part 12 by being melted with the heat generated by energizing the tip heater 3 of the spire just before injection in order to form a resin layer on an armature. The fixed and movable molds 10 and 16 are kept at 130-150 deg.C. In order to quickly raise their temperatures up to the predetermined temperature, cartridge heaters 14 and 19, which are inserted in cartridge heater holes respectively, are energized for heating and temperature raising.