Composite ply structure for tires and method of manufacture

Abstract

A tire ( 10 ) has a composite ply ( 40 ). The composite ply ( 40 ) has a primary ply ( 40 A) reinforced with parallel inextensible cords ( 41 ) and a pair of ply extensions ( 40 B) having synthetic cords ( 43 ). The method of manufacturing the tire ( 10 ) is described. The tire ( 10 ) can be made as a runflat type tire.

1 . A composite ply structure ( 40 A) as an intermediate article of manufacture for use as a carcass ply for a tire ( 10 ), the composite ply structure ( 40 ) has a primary ply ( 40 A) reinforced by cords ( 41 ), the cords ( 41 ) being encapsulated in unvulcanized rubber ( 44 ), a pair of ply extensions ( 40 B) reinforced by flexible cords ( 43 ), the flexible cords ( 43 ) being encapsulated in unvulcanized rubber ( 44 ), the ply extensions ( 40 B) each have an end ( 33 ) overlappingly joined to the primary ply ( 40 A) at a first end ( 45 ) and the other ply extension ( 40 B) being joined at a second end ( 46 ) of the primary ply ( 40 A), the composite ply ( 40 ) characterized by: 
 a joint interface ( 70 ) between the overlapping ply extensions ( 40 B) and the primary ply ( 40 A), the joint interface ( 70 ) being at least surface precured sufficient to prevent slippage of the ply extension ( 40 B) relative to the primary ply ( 40 A) during subsequent shaping and curing of the carcass.    
     
     
         2 . The composite ply ( 40 ) of  claim 1  further characterized by the overlapping joint interface ( 70 ) being at least 1 cm in width.  
     
     
         3 . The composite ply ( 40 ) of  claim 1  wherein the cords ( 41 ) of the primary ply ( 40 A) are radially oriented in the range of 65° to 90° relative to the ply length.  
     
     
         4 . the composite ply ( 40 ) of  claim 3  wherein the cords ( 43 ) of the ply extension ( 40 B) are oriented radially in the range of 65° to 90° relative to the ply length.  
     
     
         5 . The composite ply ( 40 ) of  claim 3  wherein the cords ( 43 ) of the ply extension ( 40 B) are oriented at a bias angle relative to the ply length.  
     
     
         6 . The method of preforming a composite ply ( 40 ), the composite ply ( 40 ) having a primary ply ( 40 A) and a pair of ply extensions ( 40 B) for use in the carcass of the tire ( 10 ), the method comprising the steps of: 
 cutting to a predetermined width (W A ) primary ply ( 40 A) reinforced with parallel cords ( 41 ) encapsulated in unvulcanized rubber ( 44 ), the width (W A ) extending between a first end ( 45 ) and a second end ( 46 );    applying a pair of ply extensions ( 40 B) of predetermined widths (W B ), one ply extension ( 40 B) being overlappingly joined to a first end ( 45 ) and one ply extension ( 40 B) being overlappingly joined to a second end ( 46 ), each ply extension ( 40 B) being reinforced with parallel cords ( 43 ) encapsulated in unvulcanized rubber ( 44 );    precuring the overlappingly joined ply extensions ( 40 B) to the primary ply ( 40 A) locally along the adjoining overlapping joint surfaces ( 70 ) thereby forming a composite ply ( 40 ) having a predetermined total width (WT), the composite ply being unvulcanized except at the overlapping joints ( 70 ).    
     
     
         7 . The method of preforming a composite ply ( 40 ) of  claim 6  further comprising the steps of: 
 applying an adhesive coating ( 80 ) to the adjoining overlapping joint surfaces ( 70 ) prior to curing the joint ( 70 ).  
 
     
     
         8 . The method of preforming a composite ply ( 40 ) of  claim 7  wherein the adhesive coating ( 80 ) includes induction heat sensitive material ( 82 ).  
     
     
         9 . The method of preforming a composite ply ( 40 ) of  claim 8  further comprising the steps of: 
 activating an induction field of energy along the overlapping joints ( 70 ), thereby heating the adhesive ( 80 ) sufficient to at least surface precure the joints ( 70 ).  
 
     
     
         10 . The method of preforming a composite ply ( 40 ) of  claim 9  further comprising: 
 applying force to the induction heated joints ( 70 ), thereby stitching the joint ( 70 ).