Method for manufacturing a robust tethered ball

Abstract

A process for producing a robust ball that is robustly attached to a robust tether for use in a batting practice apparatus uses a commercially available elastic shock cord (bungee cord) for the tether. An anchor is formed at one end of the tether by bending an end portion 180 degrees back upon itself where the end portion is affixed by a ring shaped clamp. The ball is composed of a high density urethane foam and is produced by a molding process. The anchor portion of the tether is inserted in the mold and an activated liquid urethane mixture is poured into the mold, where foam is formed as the reaction continues. The resulting article is capable of withstanding 5000 powerful hits with a baseball bat.

What is claimed is:  
     
         1 . A method for manufacturing a ball that is permanently and robustly attached to a tether, said method comprising the steps of: 
 folding an end portion of the tether back upon the remainder of the tether;    fastening the end portion to the remainder to produce an enlarged end on the tether;    inserting the enlarged end of the tether into a mold having a spherical cavity for producing the ball;    pouring an activated liquid polymer into the mold;    letting the activated polymer cure;    removing the mold from the cured polymer.    
     
     
         2 . The method of  claim 1  wherein the tether is a length of elastic shock cord having a core bundle of rubber strands surrounded by a cover of braided nylon.  
     
     
         3 . The method of  claim 1  wherein the polymer is urethane foam.  
     
     
         4 . An article of manufacture comprising: 
 a length of elastic shock cord having a reverted end portion;    a ball molded of urethane foam and including the reverted end portion.