Method and apparatus for manufacture of hollow bodies

Claim 2

IN A METHOD OF CONTINUALLY FORMING HOLLOW BODIES FROM THERMOPLASTIC MATERIAL IN FORM OF A SHEET, THE STEPS COMPRISING CONTINUALLY FEEDING THE SHEET STEPWISE SUBSTANTIALLY HORIZONTALLY THROUGHOUT, FOLDING THE SHEET SO THAT THE CREASE WILL BE ON TOP AND THE OPEN SIDE BELOW, THEREAFTER PREHEATING THE SHEET TO A PREHEATING TEMPERATURE BELOW THE SOFTENING TEMPERATURE, SUBSEQUENTLY HEATING THE SHEET TO A TEMPERATURE ABOVE THE SOFTENING TEMPERATURE, AND IMMEDIATELY SUBSEQUENTLY FORMING THE SHEET, AND BLOWING AGAINST THE OPEN SIDE OF SAID FOLDED SHEET FROM BELOW FOR AIR CUSHION SUSPENSION THEREOF IMMEDIATELY PRIOR TO THE FORMING.

Claim 3

IN A MACHINE, FOR USE IN THE MANUFACTURE OF HOLLOW BODIES HAVING THIN WALLS OF THERMOPLASTIC SHEET, A TRANSPORT DEVICE PROPELLING AN INVERTED U-SHAPED FOLDED THERMOPLASTIC SHEET IN A STEP-BY-STEP MANNER THROUGHOUT A PATH IN THE MACHINE, A PREHEATER ADJACENT SAID PATH OPERABLE TO HEAT THE SHEET TO A PREHEATED TEMPERATURE BELOW THE SOFTENING TEMPERATURE OF THE SHEET, A HEATER DISPOSED DOWNWARDLY OF THE PREHEATER ALONG SAID PATH AND OPERABLE TO HEAT SAID SHEET TO A TEMPERATURE ABOVE THE SOFTENING TEMPERATURE, A FORMING DEVICE DISPOSED DOWNWARDLY ALONG SAID PATH AND INCLUDING TWO OPPOSITELY MOVABLE PARTS, AND MEANS SUSPENDING SAID SHEET SUBSTANTIALLY HORIZONTAL INCLUDING A BLOWER AND A SERIES OF MOUTH PIECES FED FROM SAID BLOWER AND DISPOSED BELOW SAID PATH THROUGHOUT A SUBSTANTIALLY HORIZONTAL PORTION THEREOF AND OPERABLE TO SUSPEND THE SHEET OF SAID PORTION OF THE PATH FROM BELOW BY JET STREAM ACTION DIRECTED UPWARDLY AGAINST THE OPEN SIDE OF THE FOLDED SHEET.

Claim 4

IN A MACHINE, FOR USE IN THE MANUFACTURE OF HOLLOW BODIES HAVING THIN WALLS OF THERMOPLASTIC SHEET, A TRANSPORT DEVICE PROPELLING AN INVERTED U-SHAPED FOLDED THERMOPLASTIC SHEET IN A STEP-BY-STEP MANNER THROUGHOUT A PATH IN THE MACHINE, A PREHEATER ADJACENT SAID PATH OPERABLE TO HEAT THE SHEET TO A PREHEATED TEMPERATURE BELOW THE SOFTENING TEMPERATURE OF THE SHEET, A HEATER DISPOSED DOWNWARDLY OF THE PREHEATER ALONG SAID PATH AND OPERABLE TO HEAT SAID SHEET TO A TEMPERATURE ABOVE THE SOFTENING TEMPERATURE, A FORMING DEVICE DISPOSED DOWNWARDLY ALONG SAID PATH AND INCLUDING TWO OPPOSITELY MOVABLE PARTS, AND MEANS SUSPENDING SAID SHEET SUBSTANTIALLY HORIZONTAL INCLUDING A BLOWER AND A SERIES OF MOUTH PIECES FED FROM SAID BLOWER AND DISPOSED BELOW SAID PATH THROUGHOUT A SUBSTANTIALLY HORIZONTAL PORTION THEREOF AND OPERABLE TO SUSPEND THE SHEET OF SAID PORTION OF THE PATH FROM BELOW BY JET STREAM ACTION DIRECTED UPWARDLY AGAINST THE OPEN SIDE OF THE FOLDED SHEET.