Method and apparatus for extruding laminar wall

Claim 2

THE METOHD OF CONTINUOUSLY EXTRUDING A LAMINAR WALL OF PLASTIC COMPOUNDS IN DISTINCT, INTERBONDED LAYERS ONTO A MOVING CORE OF INDEFINITE LENGTH, AND IN WHICH ONE LAMINA IS MUCH THINNER THAN THE ADJACENT LAMINA, WHICH METHOD COMPRISES MOVING THE CORE LONGITUDINALLY THROUGH A DIE TIP, FORMING A WALL OF PLASTIC COMPOUND AROUND THE MOVING CORE BY FORCING PLASTIC COMPOUND UNDER PRESSURE THROUGH THE ANNULAR, CONICALLY-TAPERED PASSAGEWAY BETWEEN THE DIE TIP AND A DIE SURROUNDING THE SAID TIP, FORMING A THIN, INTIMATELY BONDED SKIN OF ANOTHER PLASTIC COMPOUND ON THE SAID WALL AS THE WALL IS BEING FORMED IN THE ANNULAR, CONICALLY-TAPERED PASSAGEWAY BEFORE IT REACHES THE MOVING CORE BY BLEEDING THE SECOND COMPOUND UNDER PRESSURE INTO THE INTERFACE BETWEEN THE FIRST PLASTIC COMPOUND AND A WALLFORMING SURFACE OF THE PASSAGEWAY BEFORE THE WALL ENGAGES THE MOVING CORE, AND CONTROLLING THE AMOUNT OF THE SECOND COMPOUND BLED INTO THE INTEFACE TO PRODUCE IN THE COMPLETED PRODUCT A SKIN OF THE DESIRED THICKNESS.

Claim 3

APPARATUS FOR CONTINUOUSLY EXTRUDING A WALL OF PLASTIC COMPOUND ONTO A MOVING CORE OF INDEFINITE LENGTH AND FOR SIMULTANEOUSLY FORMING A CONTINUOUS THIN SKIN OF ANOTHER PLASTIC COMPOUND INTIMATELY BONDED TO A SURFACE OF THE AFORSAID WALL COMPRISING, IN COMBINATION, AN EXTRUDING MACHINE HAVING A DIE BODY CHAMBER, A DIE HAVING AN ANNULAR, CONICALLY-TAPERED PASSAGEWAY MOUNTED IN THE WALL OF THE EXTRUDING MACHINE, SAID DIE HAVING AN ORFICE FOR DISCHARGING THE CORE AND ITS EXTRUDED COVERING, AN EXTRUSION TIP WITHIN THE EXTRUDING MACHINE FOR GUIDING THE MOVING CORE ACCURATELY INTO THE DIE, MEANS FOR FEEDING PLASTIC COMPOUND UNDER PRESSURE INTO THE DIE BODY CHAMBER THROUGH THE ANNULAR, CONICALLY-TAPERED PASSAGEWAY AND OUT OF THE DIE BODY ORIFICE WITH THE MOVING CORE, MEANS FOR BLEEDING A RELATIVELY SMALL AMOUNT OF A SECOND PLASTIC COMPOUND UNDER PRESSURE INTO THE INTERFACE BETWEEN THE FIRST PLASTIC COMPOUND AND A WALL-FORMING SURFACE OF THE EXTRUDING MACHINE WITHIN THE ANNULAR, CONICALLY-TAPERED PASSAGEWAY BEFORE THE COMPOUND REACHES THE DIE ORIFICE.

Claim 4

APPARATUS FOR CONTINUOUSLY EXTRUDING A WALL OF PLASTIC COMPOUND ONTO A MOVING CORE OF INDEFINITE LENGTH AND FOR SIMULTANEOUSLY FORMING A CONTINUOUS THIN SKIN OF ANOTHER PLASTIC COMPOUND INTIMATELY BONDED TO A SURFACE OF THE AFORSAID WALL COMPRISING, IN COMBINATION, AN EXTRUDING MACHINE HAVING A DIE BODY CHAMBER, A DIE HAVING AN ANNULAR, CONICALLY-TAPERED PASSAGEWAY MOUNTED IN THE WALL OF THE EXTRUDING MACHINE, SAID DIE HAVING AN ORFICE FOR DISCHARGING THE CORE AND ITS EXTRUDED COVERING, AN EXTRUSION TIP WITHIN THE EXTRUDING MACHINE FOR GUIDING THE MOVING CORE ACCURATELY INTO THE DIE, MEANS FOR FEEDING PLASTIC COMPOUND UNDER PRESSURE INTO THE DIE BODY CHAMBER THROUGH THE ANNULAR, CONICALLY-TAPERED PASSAGEWAY AND OUT OF THE DIE BODY ORIFICE WITH THE MOVING CORE, MEANS FOR BLEEDING A RELATIVELY SMALL AMOUNT OF A SECOND PLASTIC COMPOUND UNDER PRESSURE INTO THE INTERFACE BETWEEN THE FIRST PLASTIC COMPOUND AND A WALL-FORMING SURFACE OF THE EXTRUDING MACHINE WITHIN THE ANNULAR, CONICALLY-TAPERED PASSAGEWAY BEFORE THE COMPOUND REACHES THE DIE ORIFICE.