Method of and apparatus for manufacturing butyl inner tubes

Claim 1

A METHOD OF MANUFACTURING BUTYL RUBBER INFLATABLE TOROIDAL SHAPED ARTICLES COMPRISING THE STEPS OF FORMING A LENGTH OF TUBULAR STOCK OF BUTYL RUBBER, CUTTING SAID STOCK TO THE DESIRED LENGTH WHILE THE STOCK IS IN A FLAT POSITION, BUTTING THE FLATTENED ENDS OF SAID CUT STOCK TOGETHER TO FORM A SPLICED FLAT TUBE. PLACING THE SPLICED AREA OF THE FLAT TUBE BETWEEN SURFACES SPACED APART A DISTANCE SUBSTANTIALLY LESS THAN THE SECTIONAL DIAMETER OF THE INFLATED TUBE, INFLATING THE FLAT TUBE WITH THE SPLICED AREA POSITIONED BETWEEN SAID SURFACES SO THAT AS THE TUBE EXPANDS THE CROWN PORTION OF THE SPLICED AREA ENGAGES ONE OF SAID SURFACES AND SAID AREA IS HELD IN AN ELLIPTICAL CROSS SECTIONAL SHAPED HAVING A DIAMETER FROM THE CROWN PORTION TO RIM PORTION SMALLER THAN THE INFLATED DIAMETER OF THE TUBE, MAINTAINING THE SPLICED AREA BETWEEN SAID SURFACES UNTIL THE STOCK IN THE SPLICED AREA HAS STABILIZED, REMOVING THE SPLICED AREA FROM ENGAGEMENT WITH SAID SURFACES, PLACING THE INFLATED TUBE IN A MOLD AND CURING THE TUBE IN SAID MOLD.

Claim 2

A METHOD OF MANUFACTURING BUTYL RUBBER INFLATABLE TOROIDAL SHAPED ARTICLES COMPRISING THE STEPS OF FORMING A LENGTH OF TUBULAR STOCK OF BUTYL RUBBER, CUTTING SAID STOCK TO THE DESIRED LENGTH WHILE THE STOCK IS IN A FLAT POSITION, BUTTING THE FLATTENED ENDS OF SAID CUT STOCK TOGETHER TO FORM A SPLICED FLAT TUBE. PLACING THE SPLICED AREA OF THE FLAT TUBE BETWEEN SURFACES SPACED APART A DISTANCE SUBSTANTIALLY LESS THAN THE SECTIONAL DIAMETER OF THE INFLATED TUBE, INFLATING THE FLAT TUBE WITH THE SPLICED AREA POSITIONED BETWEEN SAID SURFACES SO THAT AS THE TUBE EXPANDS THE CROWN PORTION OF THE SPLICED AREA ENGAGES ONE OF SAID SURFACES AND SAID AREA IS HELD IN AN ELLIPTICAL CROSS SECTIONAL SHAPED HAVING A DIAMETER FROM THE CROWN PORTION TO RIM PORTION SMALLER THAN THE INFLATED DIAMETER OF THE TUBE, MAINTAINING THE SPLICED AREA BETWEEN SAID SURFACES UNTIL THE STOCK IN THE SPLICED AREA HAS STABILIZED, REMOVING THE SPLICED AREA FROM ENGAGEMENT WITH SAID SURFACES, PLACING THE INFLATED TUBE IN A MOLD AND CURING THE TUBE IN SAID MOLD.

Claim 3

AN APPARATUS FOR INFLATING SPLICED TUBES PRIOR TO CURE COMPRISING IN COMBINATION A SUPPORTING RING FOR CIRCUMFERENTIALY ENGAGING THE RIM AREA OF THE SPLICED TUBE WITH THE AXIS OF THE RING COINCIDENT WITH THE AXIS OF THE TUBE, SAID RING HAVING AN APERTURE THROUGH WHICH THE VALVE TUBE PROJECTS, MEANS FOR INFLATING THE TUBE, A SURFACE RADIALLY SPACED OUTWARDLY FROM SAID RING A DISTANCE LESS THAN THE SECTIONAL DIAMETER OF THE CURED TUBE FOR RESTRICTING RADIAL EXPANSION OF ONLY THE CROWN PORTION OF THE SPLICED AREA OF THE TUBE, SAID RESTRICTING SURFACE BEING ARCUATELY SHAPED IN AN AXIAL PLANE RELATIVE TO THE IN SAID RESTRICTING SURFACE HAVING A RADIUSE OF CURVATURE IN SAID PLANE LARGER THAN THE SECTIONAL RADIUS OF THE CURED TUBE.

Claim 4

AN APPARATUS FOR INFLATING SPLICED TUBES PRIOR TO CURE COMPRISING IN COMBINATION A SUPPORTING RING FOR CIRCUMFERENTIALY ENGAGING THE RIM AREA OF THE SPLICED TUBE WITH THE AXIS OF THE RING COINCIDENT WITH THE AXIS OF THE TUBE, SAID RING HAVING AN APERTURE THROUGH WHICH THE VALVE TUBE PROJECTS, MEANS FOR INFLATING THE TUBE, A SURFACE RADIALLY SPACED OUTWARDLY FROM SAID RING A DISTANCE LESS THAN THE SECTIONAL DIAMETER OF THE CURED TUBE FOR RESTRICTING RADIAL EXPANSION OF ONLY THE CROWN PORTION OF THE SPLICED AREA OF THE TUBE, SAID RESTRICTING SURFACE BEING ARCUATELY SHAPED IN AN AXIAL PLANE RELATIVE TO THE IN SAID RESTRICTING SURFACE HAVING A RADIUSE OF CURVATURE IN SAID PLANE LARGER THAN THE SECTIONAL RADIUS OF THE CURED TUBE.