Method and apparatus for making

Claim 1

APPARATUS FOR FORMING FINE FILAMENTS FROM A THERMOPLASITC MATERIAL, WHICH APPARATUS COMPRISES A HOLLOW CONTAINER FOR THE THERMOPLASTIC MATERIAL, SAID CONTAINER HAVING A DISCHARGE END, MEANS FOR SETTING UP A PRESSURE ON THE MATERIAL IN SAID CONTAINER AND FORCING IT TOWARD THE DISCHARGE END OF SAID CONTAINER, A PLURALITY OF SEPARATE HEATING CHAMBERS ASSOCIATED WITH THE PERIPHERY OF SAID CONTAINER, SAID HEATING CHAMBERS BEING AT A PLURALITY OF INCREASING TEMPERATURES FROM THE FEED TO THE DISCHARGE END OF SAID CONTAINER, AN EXTRUSION HOUSING SECURED TO THE DISCHARGE END OF SAID CONTAINER, SAID HOUSING HAVING A BORE ADAPTED TO RECEIVE MATERIAL FROM SAID CONTAINER, MEANS FOR HEATING SAID HOUSING TO AN ELEVATED TEMPERATURE, A DIE COMPRISING A FLAT PLATE DISPOSED TRANSVERSELY OF SAID BORE AND SECURED TO SAID HOUSING AT THE OUTER END OF ITS BORE, A MANDREL SECURED TO THE CENTER OF SAID DIE AND EXTENDING INTO THE BORE OF SAID HOUSING TO PERMIT