Method and apparatus for the manufacture of flat glass

Claim 3

APPARATUS FOR CONTINUOUSLY PRODUCING FLAT GLASS COMPRISING A MELTING FURNACE INCLUDING A DISCHARGE OUTLET FOR THE MOLTEN GLAS FORM THE FURNACE, A ROTATALY DRIVEN CASTING ROLL IN OPERATIVE ASSOCIATION WITH THE DISCHARGE OUTLET, AND MEANS FOR REGULATING THE FLOW OF MOLTEN GLASS ONTO THE CASTING ROLL WHEREBY A RIBBON OF GLASS OF DEFINITE DIMENSIONS OF WIDTH AND THICKNESS IS PRODUCED FROM THE MOLTEN GLASS DELIVERED TO THE CASTING ROLL, MEANS FOR STABILIZING THE DIMENSIONS IMPARTED TO THE RIBBON DURING CASTING, A TANK CONTAINING A BATH OF MOLTEN METAL DISPOSED IN ADVANCE OF THE CASTING ROLL IN THE DIRECTION OF ADVANCE OF TH RIBBON THEREFROM, SAID TANK BEING DISPOSED TO RECEIVE AND FLOAT THE RIBBON AS IT IS ADVANCED FROM SAID CASTING ROLL, A ROOF STRUCTUE OVER THE TANK DEFINING A HEAD SPACE OVER THE BATH, SAID ROOF STRUCTURE COMPRISING END WALLS EXTENDING UPWARDLY FROM THE TANK END WALLS AND A ROOF CONNECTING THE END WALLS, SAID END WALLS PROVIDING A NARROW INLET TO THE TANK FOR THE PREFORMED RIBBON AND A NARROW OUTLET FROM THE TANK FOR THE RIBBON, DUCT MEANS THROUGH THE ROOF STRUCTURE FOR MAINTAINING A PLENUM OF A PROTETIVE ATMOSPHERE IN THE HEAD SPACE, SAID PREFORMED RIBBON BEING ADAPTED TO FLOAT ALONG SAID BATH FROM THE INLET TO THE OUTLET OF THE TANK, AND TEMPERATURE REGULATING MEANS TO MAINTAIN IN THE BATH A DECREASING TEMPERATURE GRADIENT IN THE DIRECTION OF ADVANCE OF THE RIBBON ALONG THE BATH SO THAT NOWHERE IN THE BATH IS THE TEMPERATURE HIGHER THAN THE TEMPERATURE OF THE RIBBON SURFACE CONTACTING THE BATH, SAID TEMPERATURE REGULATING MEANS THEREBY CAUSING THE BATH TO CONTINUE THE PROGRESSIVE COOLING OF THE RIBBON AS IT IS FLOATED ALONG SAID BATH UNTIL IT IS SUFFICIENTLY COOLED TO PERMIT IT TO BE DISCHARGED WITHOUT DAMAGE FROM THE BATH.

Claim 4

APPARATUS FOR CONTINUOUSLY PRODUCING FLAT GLASS COMPRISING A MELTING FURNACE INCLUDING A DISCHARGE OUTLET FOR THE MOLTEN GLAS FORM THE FURNACE, A ROTATALY DRIVEN CASTING ROLL IN OPERATIVE ASSOCIATION WITH THE DISCHARGE OUTLET, AND MEANS FOR REGULATING THE FLOW OF MOLTEN GLASS ONTO THE CASTING ROLL WHEREBY A RIBBON OF GLASS OF DEFINITE DIMENSIONS OF WIDTH AND THICKNESS IS PRODUCED FROM THE MOLTEN GLASS DELIVERED TO THE CASTING ROLL, MEANS FOR STABILIZING THE DIMENSIONS IMPARTED TO THE RIBBON DURING CASTING, A TANK CONTAINING A BATH OF MOLTEN METAL DISPOSED IN ADVANCE OF THE CASTING ROLL IN THE DIRECTION OF ADVANCE OF TH RIBBON THEREFROM, SAID TANK BEING DISPOSED TO RECEIVE AND FLOAT THE RIBBON AS IT IS ADVANCED FROM SAID CASTING ROLL, A ROOF STRUCTUE OVER THE TANK DEFINING A HEAD SPACE OVER THE BATH, SAID ROOF STRUCTURE COMPRISING END WALLS EXTENDING UPWARDLY FROM THE TANK END WALLS AND A ROOF CONNECTING THE END WALLS, SAID END WALLS PROVIDING A NARROW INLET TO THE TANK FOR THE PREFORMED RIBBON AND A NARROW OUTLET FROM THE TANK FOR THE RIBBON, DUCT MEANS THROUGH THE ROOF STRUCTURE FOR MAINTAINING A PLENUM OF A PROTETIVE ATMOSPHERE IN THE HEAD SPACE, SAID PREFORMED RIBBON BEING ADAPTED TO FLOAT ALONG SAID BATH FROM THE INLET TO THE OUTLET OF THE TANK, AND TEMPERATURE REGULATING MEANS TO MAINTAIN IN THE BATH A DECREASING TEMPERATURE GRADIENT IN THE DIRECTION OF ADVANCE OF THE RIBBON ALONG THE BATH SO THAT NOWHERE IN THE BATH IS THE TEMPERATURE HIGHER THAN THE TEMPERATURE OF THE RIBBON SURFACE CONTACTING THE BATH, SAID TEMPERATURE REGULATING MEANS THEREBY CAUSING THE BATH TO CONTINUE THE PROGRESSIVE COOLING OF THE RIBBON AS IT IS FLOATED ALONG SAID BATH UNTIL IT IS SUFFICIENTLY COOLED TO PERMIT IT TO BE DISCHARGED WITHOUT DAMAGE FROM THE BATH.