Method for making coextruded seamless tubular tire bodies for use in pneumatic tires
AssigneeThe Firestone Tire & Rubber Company
InventorsGeorg G. A. Bohm, Thomas W. Bell
Life of this patent
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Abstract
Coextrusion from rubber of hollow tubular structures with filament reinforcement provides composites which can be formed into spliceless bodies for pneumatic tires. The composites can be formed from one, two, three or more rubber stocks and have portions or layers which can form the body plies, sidewalls, innerliners, stabilizer ply inserts and, optionally, abrasion gum strips of tire bodies. Tires made from the bodies formed from coextruded composite structures of this invention are seamless and more uniform than those made from convention tire structural components.
Claims14
A method of manufacturing seamless bodies for pneumatic tires comprising the steps of:
- (a) extruding from at least one rubber composition R.sub.1 a filament-reinforced seamless hollow tubular structure having areas of varying wall thickness along the length of the extruded filament-reinforced structure said structure having at least one layer R-I with filament reinforcement therein, and said filaments being substantially parallel to the main axis of the tubular structure;
- (b) sectioning the tubular structure in a plane substantially perpendicular to its main axis to form a hollow tubular body component;
- (c) forming separately from the tubular structure a pair of strips made from at least one layer of rubber, said strips serving to form combined abrasion gum strips and supplemental sidewall pieces and positioning the pair of strips on the tire building drum;
- (d) positioning said tubular component concentrically on a tire building drum equipped with shaping bladders and means of expansion over the pair of strips;
- (e) positioning two bead assemblies comprised of bead wires and bead fillers over the positioned tubular component;
- (f) turning up both ends of the tubular component with said shaping bladders so as to enclose the bead assemblies with a portion of the tubular component at each of its ends;
- and
- (g) expanding the center of the turned up tubular component so as to form a toroidally shaped pneumatic tire body having a body ply and sidewalls formed from the extruded structure.
A method of manufacturing seamless bodies for pneumatic tires comprising the steps of:
- (a) extruding from rubber compositions a filament-reinforced seamless hollow tubular structure having areas of varying wall thickness along the length of the extruded filament-reinforced structure said structure having at least layers R-I, R-II, R-III and R-IV wherein said filament reinforcement is in layer R-I, and said filament being substantially parallel to the main axis of the tubular structure and said layer R-IV is of an abrasion gum strip stock;
- (b) sectioning the tubular structure in a plane substantially perpendicular to its main axis to form a hollow tubular body component;
- (c) positioning said tubular component concentrically on a tire building drum equipped with shaping bladders and means of expansion;
- (d) positioning two bead assemblies comprised of bead wires and bead fillers over the positioned tubular component;
- (e) turning up both ends of the tubular component with said shaping bladders so as to enclose the bead assemblies with a portion of the tubular component at each of its ends;
- and
- (f) expanding the center of the turned up component so as to form a toroidally shaped pneumatic tire body having a body ply and sidewalls formed from the extruded structure and the body has an abrasion gum strip around each bead wire assembly formed from said layer R-IV.
Dependencies are inferred from the claim text.