Blow-molding apparatus for molding hollow plastic articles

Abstract

Abstract ROTARY BLOW-MOLDING APPARATUS IN WHICH A PLURALITY OF MOLDS ARE DISPOSED IN AN ARRANGEMENT IN WHICH THEY ARE MOVED ALONG A CLOSED PATH AT CONSTANT SPEED AND DURING THEIR TRAVEL EACH RECEIVE A SECTION OF A PARISON CONTINUOUSLY EXTRUDED IN TIMED RELATIONSHIP WITH THE TRAVEL OF THE CONTINUOUSLY TRAVELING MOLDS. THE PARISON SECTIONS ARE BLOW-MOLDED IN THE INDIVIDUAL CAVITIES OF THE MOLDS AUTOMATICALLY BY AUTOMATIC INSERTION INTO THE CAVITY OF A NEEDLE ON EACH MOLD AND RETRACTION THEREFROM. PRESSURE FLUID IS APPLIED TO THE MOLDS THROUGH THE NEEDLES SUCCESSIVELY AS THEY MOVE ALONG THE CLOSED PATH FOR BLOW-MOLDING HOLLOW ARTICLES JOINED AT THEIR NECKS. A PAIR OF TRIMMING FLEXIBLE BLADES ARE DISPOSED BETWEEN TWO SUCCESSIVE OR NEXT ADJACENT MOLDS TO TRIM EXCESS MATERIAL FROM THE MOLD BOTTOMS. THE BLADES ARE DRIVEN BY A PISTON ACTIVATING THE BLADES AUTOMATICALLY DURING ROTARY TRAVEL OF THE MOLDS. THE MOLDS EACH HAVE A FIXED HALF MOLD AND A MOBILE HALF MOLD HINGED ON THE FIXED HALF MOLD JOINTLY DEFINING A MOLD CAVITY FOR FORMING HOLLOW ARTICLES JOINED AT THEIR NECKS. OPENING AND CLOSING OF THE MOLDS IS ACCOMPLISHED BY A CAMMING GUIDE PATH I WHICH ARE SUCCESSIVELY RECEIVED CAM FOLLOWERS OPERATING THE MOBILE HALF MOLDS PROGRESSIVELY OPENING AND CLOSING THEM AND AN EJECTOR IN EACH MOLD IS ACTUATED FOR EJECTING THE MOLDED ARTICLES. EACH CONTROL OPERATION IS EXECUTED CYCLICALLY AS THE MOLDS ARE MOVED CONTINUOUSLY ALONG THE CLOSED PATH.

Inventors

• 👤 Nerio Martelli

Bibliographic Details