Cummins Inc.
PROFILED MAIN BEARING CAPS

Abstract:

A main bearing cap having a bearing cap body defining a vertical centerline, the bearing cap body having a top surface opposite a bottom surface, a pair of upper protruding parts and a pair of lower protruding parts that extend in a horizontal direction that is orthogonal to a longitudinal axis of a crankshaft, and a pair of posts that extend between the upper and the lower protruding parts. Each of the posts having a profiled side surface that is recessed to a profiled surface depth to reduce contact pressure and fretting between the bottom surface of the bearing cap and a joint surface of a bulkhead of a cylinder block when the parts are assembled. The profiled side surfaces also reduce the stiffness of the bearing cap to match more closely that of the cylinder block and direct load or force towards a centerline of the bearing cap.