Tire expanders and method of making same

Claim 1

IN A VULCANIZING MOLD HAVING A LOWER MOLD SECTION TO SUPPORT AN UNCURED DRUM-BUILT RUBBER TIRE AND A TIRE EXPANDER MOUNTED ON SAID MOLD SECTION, SAID EXPANDER HAVING A PAIR OF ALLIGNED CIRCULAR END CLOSURE DISKS, MEANS FOR MOVING SAID DISKS AXIALLY TOWARD AND AWAY FROM EACH OTHER COMPRISING A CENTRAL PISTON ROD EXTENDING THROUGH SAID MOLD SECTION AND THE LOWER END CLOSURE DISK AND CONNECTED TO THE UPPER END CLOSURE DISK, AND MEANS FOR INFLATING AND EXPANDING SAID TIRE TO A TORIC SHAPE IN THE MOLD AND FOR MAINTAINING PRESSURE IN THE TIRE TO MAINTAIN SAID SHAPE AS THE TIRE IS HEATED AND VULCANIZED IN THE MOLD, THE COMBINATION THEREWITH OF A TUBULAR DIAPHGRAM IN THE FORM OF A LENGTH OF VULCANIZED ELASTIC RUBBER TUBING THAT IS NORMALLY OF UNIFORM PERIMETER AND UNIFORM WALL THICKNESS THROUGHOUT ITS LENGTH, SAID TUBING HAVING A PERIMETER LESS THAN THAT OF SAID END CLOSURE DISKS AND HAVING ITS OPPOSITE END PORTIONS STRETCHED OVER SAID DISKS, AND MEANS CLAMPING SAID LAST-NAMED END PORTIONS AGAINST THE AXIALLY OUTER FACES OF SAID DISKS TO PROVIDE FLUID-TIGHT CONNECTIONS BETWEEN THE DISKS AND THE DIAPHRAGM, WHERE-