EXTRUSION STORAGE HEAD, METHOD FOR PRODUCTION OF BLOW-MOULDED MULTI-LAYER PLASTIC HOLLOW BODIES AND CORRESPONDING PLASTIC HOLLOW BODIES

摘要

The invention relates to an extrusion storage head ( 10 ) for a blow-molding machine and a method for production of blow-molded multi-layer plastic hollow bodies made from a two- or multi-layer pre-form, whereby two or more peripheral manifolds ( 16, 18 ) are arranged above a storage reservoir ( 20 ), from which the peripherally-extruded plastic may be sequentially ejected as a tubular parison from a controlled annular nozzle ( 24 ) by means of an ejector piston ( 22 ). According to the invention, an additional peripheral manifold ( 26 ) is arranged between the storage chamber ( 20 ) and the controlled annular nozzle ( 24 ) for application of a further plastic layer (outer functional layer) on the previously peripherally extruded plastic carrier. The additional peripheral manifold ( 26 ) is connected through a supply line ( 28 ) to an additional external storage element ( 30 ) for the molten plastic of the functional layer, wherein the additional external storage element ( 30 ) has a separate extruder ( 32 ).