Process for retreading solid tires

Abstract

A method for retreading a solid tire comprises: wrapping uncured rubber around the periphery of said tire to form a green assembly; clamping said green assembly in a C mold, said C mold comprising spindles, said spindles having a gap there between; and curing said tire assembly.

1 . An improved solid tire formed by the steps of: 
 applying uncured tread rubber to a solid tire body to form a green assembly, said solid tire body having been previously cured;    placing said green assembly in a C mold wherein said C mold comprises two halves and wherein each half comprises a spindle and wherein said spindles are dimensioned such that there is a gap therebetween when said C mold is in a closed position, said gap serving to allow said solid tire body to shrink during subsequent curing such that a portion of said solid tire body has an inner diameter that is less than the outer diameter of a corresponding rim for said solid tire body;    closing said C mold to the closed position; and    curing said green assembly within said C mold to form a cured assembly.    
   
   
       2 . The tire of  claim 1  wherein said C mold is shaped to form a smooth tread surface on the cured assembly and wherein said method further comprises the steps of: 
 removing said cured assembly from the C mold; and    carving at least one groove into the smooth tread surface of said cured assembly.    
   
   
       3 . The tire of  claim 1  wherein the diameter of said spindles is not more than about equal to the diameter of said rim.  
   
   
       4 . The tire of  claim 1  wherein said outer diameter of said spindles is about equal to said outer diameter of said rim.  
   
   
       5 . The tire of  claim 1  wherein said gap between said spindles is in the range of 25 percent to 75 percent of the width of said tire.  
   
   
       6 . The tire of  claim 1  wherein said tire is a friction based tire.  
   
   
       7 . The tire of  claim 1  wherein at least one half of said C mold comprises a tread ring and a sidewall ring and wherein said tread ring comprises a first mating surface, said sidewall ring comprises a second mating surface and wherein said first and second mating surfaces fit together when said C mold is in a closed position.  
   
   
       8 . The tire of  claim 7  wherein said first mating surface has a frustoconical shape.  
   
   
       9 . The tire of  claim 7  wherein said tread ring is notched such that a cavity is formed between said sidewall ring and said tread ring when said C mold is in a closed position, said cavity serving to hold excess rubber extruded from said green assembly when said C mold is closed.  
   
   
       10 . The tire of  claim 1  wherein said solid tire body is formed to a desired shape by buffing.  
   
   
       11 . The tire of  claim 1  wherein said spindles are dimensioned such that: 
 at least a portion of said spindles meet when said C mold is in a closed position; and    said spindles comprise alternative gap means wherein said alternative gap means are dimensioned such that a portion of the internal diameter of said solid tire body shrinks during said curing.    
   
   
       12 . The tire of  claim 11  wherein said alternative gap means comprise holes in said spindles or grooves in said spindles.  
   
   
       13 . The tire of  claim 1  wherein said tire has a size in the range of 9-5-5 to 36-16-30 or 4.00-8 to 14:00-24.