Rail road car truck and members therefor

Abstract

A rail road freight car truck has a truck bolster and a pair of side frames, the truck bolster being mounted transversely relative to the side frames. The mounting interface between the ends of the axles and the sideframe pedestals allows lateral rocking motion of the sideframes in the manner of a swing motion truck. The lateral swinging motion is combined with a longitudinal self steering capability. The self steering capability may be obtained by use of a longitudinally oriented rocker that may tend to permit resistance to deflection that is proportional to the weight carried across the interface. The truck may have auxiliary centering elements mounted in the pedestal seats, and those auxiliary centering elements may be made of resilient elastomeric material. The truck may also have friction dampers that have a disinclination to stick-slip behavior. The friction dampers may be provided with brake linings, or similar features, on the face engaging the sideframe columns, on the slope face, or both. The friction dampers may operate to yield upward and downward friction forces that are not overly unequal. The friction dampers may be mounted in a four-cornered arrangement at each end of the truck bolster. The spring groups may include sub-groups of springs of different heights.