Plastic mixing and injection system

Abstract

Abstract METHOD AND APPARATUS FOR PREPARING FOR AND DIRECTING A MIXTURE OF PLASTIC MATERIAL AND FILLER MATERIAL INTO MOLDING DIES TO FORM AND ARTICLE OF MANUFACTURE. PREPARATION INCLUDES THE MELTING OF A THERMOPLASTIC MATERIAL IN A HEATED RECEPTACLE AND CONTINUOUSLY CIRCULATING THE MELTED PLASTIC THROUGH AND THE RECEPTACLE WITH TEMPERATURE CONTROL. A TRANSFER VALVE MAY BE OPERATED TO DIVERT THE CIRCULATING PLASTIC MATERIAL TO A HEATED MIXING RECEPTACLE WHERE FILLER MATERIAL IS ADDED, THE TEMPERATURE BEING CONTROLLED TO ASSURE COMPLETE WETTING AND MIXING OF THE FILLER MATERIAL BY AND WITH THE LIQUID PLASTIC. CONTINUOUS CIRCULATION THROUGH THE MIXING RECEPTACLE MAINTAINS THE FILLER MATERIAL IN MECHANICAL SUSPENSION IN THE MIXTURE. A SECOND TRANSFER VALVE MAY BE OPERATED TO DIVERT THE MIXTURE INTO A HEATED HOLDING RECEPTACLE FOR CONTINUOUS CIRCULATION THERETHROUGH AND, AS NEEDED, FOR CONVEYANCE TO MOLDING DIES. SUITABLE VALVE MEANS ARE PROVIDED TO DIVERT FLOW TO THE DIES THROUGH AN INJECTION GUN. UPON FILLING HE DIES, A MULTIPLE CYLINDERED INJECTION MACHINE PRESSURIZES THE MIXTURE THROUGH THE GUN TO ELIMINATE VOILDS IN THE MOLDED ARTICLE AND TO COMPENSATE FOR SHRINKAGE AS THE MIXTURE COOLS.

Inventors

• 👤 Stirling A Mcinnis

Bibliographic Details