Apparatus for forming multilayer thermoplastic resin extrusions

Claim 1

Improved apparatus for forming multilayer, thermoplastic resin extrusions, comprising in combination: first extruder means for plasticizing a first thermoplastic resin; second extruder means for plasticizing a second thermoplastic resin; die means for shaping said multilayer resins to the desired configuration; injector means in fluid communication with said first and second extruder means and with said die means, said injector means including injector housing means having a resin flow passageway extending therethrough and a transverse passageway extending therethrough intersecting said flow passageway; first and second transverse housing members removeably located in said transverse passageway in sealing engagement with said injector housing means on each side of said flow passageway, said transverse housing members having recesses in juxtaposed ends thereof forming a portion of said flow passageway, having second recesses in each said end adjacent to said flow passageway and having a port extending into one of said second recesses; means connecting the port in said transverse housing member to said second extruder means for receiving plasticized resin therefrom; and, an injector body member removeably located in said second recesses supported by said housing members and extending across said flow passageway whereby said first plasticized resin is divided into two layers, said body member having a cavity therein in fluid communication with said port and having a slot extending into said cavity whereby a layer of said second plasticized resin can be deposited between said divided layers of said first plasticized resin.