The design of overlapped crankshafts Part 1: Crankpin fillets

Abstract

The finite element (FE) technique, with two-dimensional (plane strain) and three- dimensional meshes, has been used to determine the surface stress distributions in 19 shapes of undercut crankpin fillets under radial bending due to the connecting rod force and under pure torsion. In radial bending, two-dimensional analyses are as valid as three-dimensional ones. The stress concentration factors (SCFs) are compared with symmetrically notched and shouldered bars in pure bending. The information in this paper helps the designer to obtain low stress concentration factors in multi-circular arc or spiral fillets of chosen axial and radial extents.