Power transmission belt and method

Abstract

The invention comprises a belt having a plied construction overlying tensile cords. An elastomeric layer overlies an overcord which overlies yet another elastomeric layer which in turn overlies a tensile cord. The overcord layer supports the tensile cords during molding thereby stabilizing a cordline centerline position with respect to a rib apex. This construction significantly reduces a distance from a tensile cord centerline to a rib apex and rib/pulley interface in a multi-ribbed belt, thereby significantly increasing belt life.

I claim:  
     
         1 . A method of building a belt comprising the steps of: building a belt build comprising the steps of; 
 plying a first elastomeric layer on a build mandrel, the build mandrel having an expandable outer surface;    plying a substantially non-porous cross-cord layer on the elastomeric layer;    plying a second elastomeric layer on the cross-cord layer;    spiraling a tensile member on the second elastomeric layer; and    plying a third elastomeric layer on the tensile cord;    pressurizing the expandable outer surface thereby pressing the belt build into a mold having a belt profile;    supporting the tensile member with the cross-cord layer whereby a tensile cord position is controlled;    applying a temperature to the belt build;    curing the belt; and    removing the belt build from the mold.    
     
     
         2 . The method as in  claim 1  further comprising the step of plying a non-woven material on the third elastomeric layer.  
     
     
         3 . The method as in  claim 1  further comprising the step of using a multi-ribbed profile having rib apexes.  
     
     
         4 . The method as in  claim 3  further comprising the step of cutting the cured belt build.  
     
     
         5 . The method as in  claim 1  further comprising the step of using a fiber loading in the first elastomeric layer.  
     
     
         6 . The method as in  claim 1  further comprising the step of using a fiber-loading in the third elastomeric layer.  
     
     
         7 . The method as in  claim 1  further comprising the step of forming the second elastomeric solely of rubber.  
     
     
         8 . The method as in  claim 1 , further comprising the step of forming a gap between ends of the first elastomeric layer.  
     
     
         9 . The method as in  claim 1 , further comprising the step of forming a butt-splice between ends of the first elastomeric layer.