Method and apparatus for reducing shoulder wear on testing wheel

Abstract

The present invention includes methods and apparatus for testing tire performance using a laterally-contoured road wheel. Accordingly, particular embodiments of the machine include a wheel configured to rotate, the wheel having a tire operating surface configured to engage a tire during operation, the outer tire operating surface arranged along an annular side of the wheel and having a width extending laterally relative a circumferential direction of the wheel along a contoured path. The machine may further include a drive source configured to rotate the wheel and a tire mount configured to rotatably maintain a tire. The present invention also includes methods of forming a laterally-contoured tire operating surface for a road wheel.

What is claimed is: 
     
         1 . A method of testing tire performance using a wheel, the method comprising the steps of:
 providing a single wheel configured to rotate, the wheel having a tire operating surface arranged along an outer annular side of the wheel and configured to engage a tire during operation, the tire operating surface having a width extending laterally relative a circumferential direction of the wheel and along a non-linear path and including a convex portion wherein the tire operating surface is symmetrical relative a plane bisecting the width of the tire operating surface, where the non-linear path defines the convex portion arranged between a pair of counter-curvature portions in an axial direction of the wheel, the pair of counter-curvature portions forming a concave side of the wheel;   engaging forcefully a tread of a tire against the tire operating surface of the wheel; and,   rotating the tire and the wheel while engaged according to the prior step for a sufficient duration to evaluate the tire.   
     
     
         2 . The method of  claim 1 , where the tire operating surface tapers radially inward toward a rotational axis of the wheel as the surface extends laterally in a direction away from a centerline of the tire operating surface, the centerline extending circumferentially around the tire operating surface. 
     
     
         3 . The method of  claim 1 , where the convex portion is defined by a constant radius of curvature. 
     
     
         4 . The method of  claim 3 , where the radius of curvature has an origin located at an intersection of the plane and a rotational axis of the wheel. 
     
     
         5 . The method of  claim 3 , where the radius of curvature has an origin located along the plane and between a rotational axis of the wheel and the tire operating surface. 
     
     
         6 . The method of  claim 3 , where the radius of curvature has an origin located along the plane such that the rotational axis of the wheel is located between the tire operating surface and the origin. 
     
     
         7 . The method of  claim 1 , where the non-linear path is defined by two or more different radii of curvatures. 
     
     
         8 . The method of  claim 1 , where the non-linear path provides a non-linear portion arranged between a pair of cylindrical portions. 
     
     
         9 . A machine for testing tire performance, the machine comprising:
 a single wheel configured to rotate, the wheel having a tire operating surface arranged along an outer annular side of the wheel and configured to engage a tire during operation, the tire operating surface having a width extending laterally relative a circumferential direction of the wheel and along a non-linear path and including a convex portion wherein the tire operating surface is symmetrical relative a plane bisecting the width of the tire operating surface, where the non-linear path defines a convex, central portion arranged between a pair of counter-curvature portions in an axial direction of the wheel, the pair of counter-curvature portions forming a concave side of the wheel;   a drive source configured to rotate the wheel;   a tire mount configured to rotatably maintain a tire and forcefully maintain the tire against the wheel.   
     
     
         10 . The machine of  claim 9 , where the tire operating surface tapers radially inward toward a rotational axis of the wheel as the surface extends laterally in a direction away from a centerline of the tire operating surface, the centerline extending circumferentially around the tire operating surface. 
     
     
         11 . The machine of  claim 10 , where at least a portion of the width of the tire operating surface extends laterally along a convex portion to form a laterally convex tire operating surface and the width of the tire operating surface is greater than a width of a tire. 
     
     
         12 . The machine of  claim 11 , where the convex portion is defined by a constant radius of curvature. 
     
     
         13 . The machine of  claim 9 , where at least a portion of the non-linear path is defined by a constant radius of curvature. 
     
     
         14 . The machine of  claim 12 , where the radius of curvature has an origin located at an intersection of the plane and a rotational axis of the wheel. 
     
     
         15 . The machine of  claim 12 , where the radius of curvature has an origin located along the plane and between a rotational axis of the wheel and the tire operating surface. 
     
     
         16 . The machine of  claim 12 , where the radius of curvature has an origin located along the plane such that a rotational axis of the wheel is located between the tire operating surface and the origin. 
     
     
         17 . The machine of  claim 9 , where the non-linear path is defined by two or more different radii of curvatures. 
     
     
         18 . The machine of  claim 9 , where the non-linear path provides a non-linear portion arranged between a pair of cylindrical portions.