Method and apparatus for forming flexible hollow tubing

Claim 1

THE PROCESS OF MANUFACTURING FLEXIBLE HOLLOW TUBING OF SYNTHETIC RESINOUS MATERIAL COMPRISING THE STEPS OF EXTRUDING A STRIP OF SYNTHETIC RESINOUS MATERIAL HAVING AT LEAST ONE WING PORTION AT A CONTROLLED LINEAR RATE, SECURING SAID STRIP TO A CYLINDRICAL SURFACE, ROTATING SAID CYLINDRICAL SURFACE ABOUT ITS CENTRAL AXIS IN A FIRST ROTATIONAL DIRECTION AND TRANSLATING SAID CYLINDRICAL SURFACE ALONG SAID CENTRAL AXIS IN A FIRST LINEAR DIRECTION AT RATES COMPLEMENTARY TO THE CONTROLLED LINEAR EXTRUSION RATE, FORMING SAID STRIP OF LINEAR MATERIAL INTO AN OVERLAPPED HELIX ON SAID CYLINDRICAL SURFACE WITH EACH TURN OF SAID STRIP OF LINEAR MATERIAL AT LEAST PARTIALLY OVERLAPPING THE WING PORTION OF THE PREVIOUSLY APPLIED TURN, REMOVING SAID HELICALLY OVERLAPPED MATERIAL FROM SAID CYLINDRICAL SURFACE AFTER IT HAS COOLED AND SOLIDIFIED INTO A FIRST HOLLOW TUBING, SECURING A FURTHER PORION OF SAAID STRIP TO SAID CYLINDRICAL SURFACE, ROTATING SAID CYLINDRICAL SURFACE ABOUT ITS CENTRAL AXIS IN A SECOND ROTATIONAL DIRECTION OPPOSITE FROM SAID FIRST ROTATIONAL DIRECTION AND TRANSLATING SAID CYLINDRICAL SURFACE ALONG SAID CENTRAL AXIS IN A SECOND LINEAR DIRECTION OPPOSITE FROM SAID FIRST DIRECTION AT RATES COMPLEMENTARY TO THE CONTROLLED LINEAR EXTRUSION RATE, AND FORMING A SECOND HOLLOW TUBING IN THE MANNER STATED ABOVE FOR THE FIRST HOLLOW TUBING.