Hopper car having double-curved side walls

Abstract

A hopper car having double-curved side walls for transporting bulk solids. The car has side walls, end walls, and a bottom which are all joined to present a container for transporting the bulk solids. The bottom presents at least one opening for discharge of the bulk solid. Each side wall presents upper and lower convex sections forming an indentation at approximately the vertical center of the side wall.

1 . A hopper car for transporting bulk solids, said car comprising:
 opposed generally upright side walls each presenting upper and lower convex sections forming an indentation at approximately the vertical center of said side wall;   opposed generally upright end walls joined to each of said side walls; and   a bottom joined with each of said side walls and each of said end walls, said bottom presenting an opening for discharge of the bulk solid.   
   
   
       2 . The car of  claim 1 , wherein each of said side walls includes a concave portion extending in a longitudinal direction to reduce the width of said car in its midsection thereby providing additional clearance on curved portions of track. 
   
   
       3 . The car of  claim 2 , wherein each of said side walls includes first and second end portions each joined with one of said end walls, wherein said concave portion extends between said first and second end portions, and wherein each of said first and second end portions presents upper and lower convex sections forming an indentation at approximately the vertical center of said side wall. 
   
   
       4 . The car of  claim 1 , wherein said convex sections have approximately equal curvature. 
   
   
       5 . The car of  claim 4 , wherein the radius of curvature of said convex sections is between 95 to 120 inches. 
   
   
       6 . The car of  claim 1 , further comprising a convex cover joined to said side and end walls. 
   
   
       7 . The car of  claim 6 , wherein said cover and convex sections have approximately equal curvature. 
   
   
       8 . The car of  claim 7 , wherein the radius of curvature of said cover and convex sections is between 95 to 120 inches. 
   
   
       9 . The car of  claim 1 , further comprising a first reinforcing member joined to each side wall extending along approximately the top of said wall, a second reinforcing member joined to each side wall extending along said indentation, and a third reinforcing member joined to each side wall extending along approximately the base of said lower section. 
   
   
       10 . The car of  claim 1 , wherein said bottom presents a plurality of openings for discharge of the bulk solid, each side wall presents a plurality of discharge sections corresponding with said openings, each discharge section extends down from said lower section and joins with said bottom adjacent one of said openings, and said car further comprises inverted V-shaped structures joined with said bottom between adjacent openings. 
   
   
       11 . The car of  claim 1 , further comprising a discharge gate coupled with said bottom adjacent said opening for regulating discharge of the bulk solid through said opening.