Patent ID: 6045742
Filing Date: 2000-04-04
Classification: B29C

Abstract:
A method for applying a differential pattern of heating zones to a resin material for injection into a mold cavity as it passes through an injection nozzle, said method comprising the steps of:providing a conduit for feeding resin melt through an injection nozzle body along a feed path directed to a mold cavity;wrapping the injection nozzle body with a continuous coil winding of heating elements;distributing the heat from said coiled heating elements uniformly by interposing a heat conductive sheath between the coiled heating elements and the injector nozzle body;forming a series of heat insulting circumferential grooves along the inside surface of the sheath that is in heat conductive contact with the injector nozzle body, said grooves extending generally normal to the feed path of the resin melt;whereby a differential pattern of heating zones is applied to the resin melt.