초록 ▼

A multi-cavity injection mold, for simultaneously injection molding a plurality of multi-layer articles, having a single hot runner manifold system for the sequential supply of first and second molten molding materials to the cavities of the mold with each of the materials being supplied simultaneou

A multi-cavity injection mold, for simultaneously injection molding a plurality of multi-layer articles, having a single hot runner manifold system for the sequential supply of first and second molten molding materials to the cavities of the mold with each of the materials being supplied simultaneously to all cavities in equal quantities. The invention also provides a core rod for each cavity in which a concavity is provided, adjacent the entry point of the materials into the cavity, to prevent the first injected material in an injection cycle from being washed from the end of the core rod by the second injected material, a buffer of the first injected material in the neck region of the preform to compensate for variations in temperature of the cavities and material being distributed to different parts of the mold and the use of the first part of the metered quantity of the first to be injected material from the next injection cycle to seal the preform at the end of the injection cycle.

대표청구항 ▼

A multi-cavity injection mold for simultaneously injection molding a plurality of multi-layer articles comprising: a mold structure defining a plurality of mold cavities and a single hot runner manifold system for supplying said plurality of cavities with a first and second plastic material, said si

A multi-cavity injection mold for simultaneously injection molding a plurality of multi-layer articles comprising: a mold structure defining a plurality of mold cavities and a single hot runner manifold system for supplying said plurality of cavities with a first and second plastic material, said single hot runner manifold system providing a single branched path for sequential contiguous supply of said first plastic material, simultaneously in substantially equal quantities to each of said plurality of cavities, and said second plastic material, simultaneously in substantially equal quantities, to each of said plurality of cavities along said single branched path; temperature control means for maintaining said hot runner manifold system and said cavities at desired temperatures; and valve means for sequentially supplying desired contiguous quantities of said first and said second materials from respective first and second plastic material sources to said hot runner manifold system for contiguous sequential passage of said plastic materials through said single branched path to each said cavity.