Extrusion method and apparatus

Claim 1

A METHOD OF SHAPING HIGHLY VISCOUS PLASTIC STOCK WHICH IS SUBJECT TO SCORCHING AND HEAT-CURING AT ELEVATED TEMPERATURE COMPRISING IN COMBINATION THE STEPS OF ADVANCING THE STOCK AT A TEMPERATURE SUFFICIENTLY ELEVATED TO RENDER THE STOCK READILY WORKABLE, BUT INSUFFICIENTLY ELEVATED TO CAUSE SCORCHING OF THE STOCK, INJECTING THE SAID ADVANCING STOCK THROUGH A RESTRICTED DIE ORIFICE INTO A SHAPING CHAMBER, AND SUDDENLY FURTHER HEATING THE STOCK AS THE STOCK PASSES INTO THE RESTRICTED DIE ORIFICE TO PRODUCE A SUBSTANTIAL SUDDEN RISE IN THE TEMPERATURE OF THE STOCK AT THE INSTANT THAT IT PASSES INTO THE SAID DIE.

Claim 2

A METHOD OF SHAPING HIGHLY VISCOUS PLASTIC STOCK WHICH IS SUBJECT TO SCORCHING AND HEAT-CURING AT ELEVATED TEMPERATURE COMPRISING IN COMBINATION THE STEPS OF ADVANCING THE STOCK AT A TEMPERATURE SUFFICIENTLY ELEVATED TO RENDER THE STOCK READILY WORKABLE, BUT INSUFFICIENTLY ELEVATED TO CAUSE SCORCHING OF THE STOCK, INJECTING THE SAID ADVANCING STOCK THROUGH A RESTRICTED DIE ORIFICE INTO A SHAPING CHAMBER, AND SUDDENLY FURTHER HEATING THE STOCK AS THE STOCK PASSES INTO THE RESTRICTED DIE ORIFICE TO PRODUCE A SUBSTANTIAL SUDDEN RISE IN THE TEMPERATURE OF THE STOCK AT THE INSTANT THAT IT PASSES INTO THE SAID DIE.

Claim 3

AN APPARATUS FOR SHAPING HIGHLY VISCOUS AND HEATSENSITIVE PLASTIC STOCKS COMPRISING IN COMBINATION AN EXTRUDER BODY, SAID EXTRUDER BODY BEING PROVIDED WITH HEATING MEANS FOR HEATING PLASTIC STOCK WITHIN THE EXTRUDER BODY TO WORKING TEMPERATURE, AN EXTRUSION SCREW ROTATABLY MOUNTED IN SAID EXTRUDER BODY FOR VERY GRADUAL ROTATION TO ADVANCE THE STOCK THROUGH SAID EXTRUDER BODY, A TRANSVERSE CROSS HEAD SECURED TO THE DELIVERY END OF SAID EXTRUDER BODY, A DIE MEMBER MOUNTED IN SAID CROSS HEAD, A STATIONARY SUPPORTING SLEEVE EXTENDING WITHIN SAID HEAD AXIALLY OF THE SAID DIE INTO PROXIMITY TO THE ENTRANCE OF THE DIE, A ROTARY HEAD MOUNTED AT THE END OF SAID SLEEVE IMMEDIATELY ADJACENT TO THE ENTRANCE TO SAID DIE AND COAXIAL THEREWITH FOR HIGH SPEED ROTATION TO GENERATE INTENSE AND SUDDEN HEATING WITHIN THE PLASTIC AT THE INSTANT THAT THE PLASTIC STREAMS INTO SAID DIE UNDER THE INFLUENCE OF SAID EXTRUSION SCREW, THE SAID ROTARY HEAD BEING FRUSTRO-CONICAL AND HAVING A SUBSTANTIAL LENGTH IN COMPARISON WITH ITS MAXIMUM DIAMETER, AND THE SAID ROTARY HEAD BEING IN ADDITION TO AND SEPARATE FROM SAID ROTARY SCREW, SAID STATIONARY SUPPORTING SLEEVE HAVING AN INTERNAL PASSAGE FOR CIRCULATING COOLING FLUID THERETHROUGH TO PREVENT SAID ROTARY HEAD AND THE PORTIONS OF THE SUPPORTING SLEEVE ADJACENT THERETO FROM BECOME EXCESSIVELY HOT, AND A SHAPING CHAMBER MOUNTED AT THE DELIVERY END OF SAID DIE FOR RECEIVING THE THUS INTENSELY HEATED PLASTIC.

Claim 4

AN APPARATUS FOR SHAPING HIGHLY VISCOUS AND HEATSENSITIVE PLASTIC STOCKS COMPRISING IN COMBINATION AN EXTRUDER BODY, SAID EXTRUDER BODY BEING PROVIDED WITH HEATING MEANS FOR HEATING PLASTIC STOCK WITHIN THE EXTRUDER BODY TO WORKING TEMPERATURE, AN EXTRUSION SCREW ROTATABLY MOUNTED IN SAID EXTRUDER BODY FOR VERY GRADUAL ROTATION TO ADVANCE THE STOCK THROUGH SAID EXTRUDER BODY, A TRANSVERSE CROSS HEAD SECURED TO THE DELIVERY END OF SAID EXTRUDER BODY, A DIE MEMBER MOUNTED IN SAID CROSS HEAD, A STATIONARY SUPPORTING SLEEVE EXTENDING WITHIN SAID HEAD AXIALLY OF THE SAID DIE INTO PROXIMITY TO THE ENTRANCE OF THE DIE, A ROTARY HEAD MOUNTED AT THE END OF SAID SLEEVE IMMEDIATELY ADJACENT TO THE ENTRANCE TO SAID DIE AND COAXIAL THEREWITH FOR HIGH SPEED ROTATION TO GENERATE INTENSE AND SUDDEN HEATING WITHIN THE PLASTIC AT THE INSTANT THAT THE PLASTIC STREAMS INTO SAID DIE UNDER THE INFLUENCE OF SAID EXTRUSION SCREW, THE SAID ROTARY HEAD BEING FRUSTRO-CONICAL AND HAVING A SUBSTANTIAL LENGTH IN COMPARISON WITH ITS MAXIMUM DIAMETER, AND THE SAID ROTARY HEAD BEING IN ADDITION TO AND SEPARATE FROM SAID ROTARY SCREW, SAID STATIONARY SUPPORTING SLEEVE HAVING AN INTERNAL PASSAGE FOR CIRCULATING COOLING FLUID THERETHROUGH TO PREVENT SAID ROTARY HEAD AND THE PORTIONS OF THE SUPPORTING SLEEVE ADJACENT THERETO FROM BECOME EXCESSIVELY HOT, AND A SHAPING CHAMBER MOUNTED AT THE DELIVERY END OF SAID DIE FOR RECEIVING THE THUS INTENSELY HEATED PLASTIC.