Adapter for coextrusion apparatus

Claim 2

An extrusion adapter as set forth in claim 2 where the pair of spaced downwardly directed passageways in the upper adapter body are divergingly disposed and the complementary pair of spaced passageways in the lower adapter body which communicate therewith are convergingly disposed.

Claim 3

An extrusion adapter as set forth in claim 2 where the transversely disposed bore in the upper adapter body which communicates with the vertically disposed passageway therein is of greater length than said vertically disposed passageway and constitutes a valve seat for said plug valve, and where said plug valve is provided with a cut-away portion located in alignment with said vertically disposed passageway and extending substantially the full leNgth thereof, said cut-away portion comprising a pair of upwardly inclined side surfaces and a pair of upwardly inclined top surfaces constituting a tapered apex.

Claim 4

An extrusion adapter as set forth in claim 4 including means for selectively rotating said plug valve from a central position, where a stream of resin entering the vertically disposed passageway in the upper extruder body may flow through both aligned pairs of downwardly directed passageways, to one of two adjusted positions where flow of said resin will be restricted to one of said aligned pairs of downwardly directed passageways.

Claim 5

An extrusion adapter as set forth in claim 5 where the extremities of said plug valve are externally threaded for engagement with locking means for retaining said plug valve in adjusted position and where one of said threaded extremities is provided with opposed flattened surfaces to permit ready rotative adjustment of said plug valve.

Claim 6

Extrusion apparatus for the coextrusion of a flat sheet of multiple layered thermoplastic film, said apparatus including a first extruder and a die provided with an interior manifold and an elongated and narrow discharge orifice; conduit means for delivering a heat plasticized stream of thermoplastic resin from said first extruder to said die manifold; an adapter mounted in said conduit means, said adapter including mating upper and lower body portions; said upper adapter body being provided with a transverse bore and having a substantially centrally located passageway in the top surface thereof communicating with said transverse bore, said upper body portion also being provided with a pair of spaced downwardly directed passageways extending from said transverse bore through the bottom surface of the upper adapter body; a pair of complementarily spaced downwardly directed passageways extending through the lower adapter body in direct communication with the pair of passageways in the upper adapter body; a plug valve mounted within said transverse bore for rotative movement and adjustable to permit heat plasticized resin from said first extruder to flow selectively through at least one of said aligned pairs of spaced passageways into the die manifold; a centrally located cavity in said lower adapter body and a substantially centrally located passageway in the bottom surface of the lower adapter body intermediate the pair of spaced passageways therein providing communication between said centrally located cavity and the die manifold; a second extruder; and conduit means connecting said second extruder with said centrally located cavity to permit heat plasticized resin from said second extruder to flow through the centrally located passageway in the lower die body into the die manifold as a stream immediately adjacent to a stream of resin from the first extruder flowing through either one of said aligned pair of spaced passageways.

Claim 7

Extrusion apparatus as set forth in claim 7 where the transversely disposed bore in the upper adapter body which communicates with the vertically disposed passageway therein is of greater length than said vertically disposed passageway and constitutes a valve seat for said plug valve, and where said plug valve is provided with a cut-away portion located in alignment with said vertically disposed passageway and extending substantially the full length thereof, said cut-away portion comprising a pair of upwardly inclined side surfaces and a pair of upwardly inclined top surfaces constituting a tapered apex.

Claim 8

Extrusion apparatus as set forth in claim 8 including means for selectively rotating said plug valve from a central position, where a stream of resin entering the vertically disposed passageway in the upper extruder body may flow through both aligned pairs of downwardly directed passageways, to one of two adjusted positions where flow of said resin will be restricted to one of said aligned pairs of downwardly directed passageways.